Author Archive

ntp offset – use ntpdate to manually sync local time with ntp server

February 2nd, 2012 1 comment

Here's the outline for resolution:

1.check whether ntpd is running on the problematic host;

2.stop ntpd;

3.use ntpdate to manually sync with ntp server

4.start up ntpd.

Here's the detailed commands:

root@testhost# service ntpd stop
Shutting down ntpd: [ OK ]
root@testhost# ps -ef|grep ntp
root 9805 9542 0 01:53 pts/0 00:00:00 grep ntp
root@testhost# cat /etc/ntp.conf
tinker panic 0
server timehost1 prefer
server timehost2
server timehost3
driftfile /var/lib/ntp/drift

# Prohibit general access to this service.
restrict default ignore

# Permit the cluster node listed to synchronise with this time service.
# Do not permit those systems to modify the configuration of this service.
# Allow this host to be used as a timesource

# Permit all loopback interface access.
root@testhost# ntpdate -u timehost1
2 Feb 01:55:20 ntpdate[9824]: step time server offset 59.998407 sec
root@testhost# service ntpd start
Starting ntpd: [ OK ]
root@testhost# ps -ef|grep ntp
ntp 9999 1 0 01:55 ? 00:00:00 ntpd -u ntp:ntp -p /var/run/ -g
root 10017 9542 0 01:55 pts/0 00:00:00 grep ntp


  • If your host is a Virtual Machine running on Xen hypervisor, then you may find that ntpdate or ntpd will fail to synchronize time with the time server. That's because the VM will sync with hypervisor by default. So if you want to sync your VM's time with the time server, there're two methonds:

1. Synchronize time on XEN hypervisor and the VM will then sync with it automatically;

2. If you just want to sync VM's time without change XEN hypervisor's time setting, then on the VM, do the following:

echo 1 > /proc/sys/xen/independent_wallclock #or in /etc/sysctl.conf, xen.independent_wallclock=1

After this step, you can now sync time for the VM without impacting others.

  • You can use ntpq -p to check the status of remote time servers.

[root@test-host ~]# ntpq -p
remote refid st t when poll reach delay offset jitter
*LOCAL(0) .LOCL. 5 l 66 64 377 0.000 0.000 0.001 .INIT. 16 u - 512 0 0.000 0.000 0.000 .INIT. 16 u - 512 0 0.000 0.000 0.000

On column "remote", we can see that it's blank space before and, this means that the two sources are discarded, failed sanity check and has never been synced to.

For more details about output of ntpq -p, you can read the explanation here.

  • For ntpd firewall issue, if you want to use ntpd, then you need to fix your network/firewall/NAT so that ntpd can have full unrestricted access to UDP port 123 in both directions. Also, you may setup one cronjob to bounce ntpd every hour so that ntp will be forced to sync with time server. echo "`tr -cd 1-5 </dev/urandom | head -c 2` */1 * * * root /sbin/service ntpd restart" >> /etc/crontab #you can of course manully add to cronjob via crontab -e -u root
  • Many people have difficulties with using RESTRICT. They want to set themselves up to be as secure as possible, so they create an extremely limited default RESTRICT line in their /etc/ntp.conf file, and then they find that they can't talk to anyone. If you're having problems with your server, in order to do proper debugging, you should turn off all RESTRICT lines in your /etc/ntp.conf file, and otherwise simplify the configuration as much as possible, so that you can make sure that the basic functions are working correctly. Once you get the basics working, try turning back on various features, one-by-one. Here some tips for ntp restrict keyword controlling ntpd access.
  • To get start with ntp, read this guide(explained server & peer & stratum. Pool is a list of servers). And here is the full document about ntp.

using timex to check whether performance degradation caused by OS or VxVM

February 1st, 2012 No comments

To check for differences between operating system times to access disks and Volume Manager times to access disks, we can know whether to check for differences between operating system times to access disks and Volume Manager times to access disks. This is because they should both be about the same since both commands force a read of disk header information. If one of those is markedly greater then it indicates a problem in that area.

#echo | timex /usr/sbin/format #to avoid prompt for user input. Use time instead of timex for linux
real          13.03

user           0.10

sys            1.49
#timex vxdisk –o alldgs list
real           2.65

user           0.00

sys            0.00

Categories: IT Architecture, Kernel, Linux, Systems, Unix Tags:

start/stop syslogd on solaris 10 or solaris 8/9

January 21st, 2012 1 comment

Here's the configuration:

On Solaris 5.8 and 5.9, at the command prompt, enter /etc/init.d/syslog stop, followed by /etc/init.d/syslog start.

On Solaris 5.10, at the command prompt, enter svcadm disable svc:/system/system-log && svcadm enable svc:/system/system-log.

Now you can check ps -ef|grep syslogd, and to configure syslog, go to /etc/syslogd.conf. Log files for syslogd is under /var/log/syslog.

replace a broken disk under solaris svm control

January 12th, 2012 No comments

Firstly, you need detach the submirror that need replaced(save a copy of metastat -i/-p, metadb -i, df -k before doing these steps):

metadetach d0 d10 #d10 is c0t0d0 in this context

If you met error like:

attempt an operation on a submirror that has erred components

Then you'll need do a -f with metadetach:

metadetach -f d0 d10

Now do a check that all SVM objects have been removed from the failing disk:

metastat -p | grep c0t0d0
metadb | grep c0t0d0

Insert the new disk now.

Now configure the new disk:(this step may not needed if the disk is there in the output of metastat -i)

cfgadm -c configure c1::dsk/c0t0d0

Verify the disk has a "configured".

copy disk head info from c1t0d0(the good one) to c1t1d0(the replaced one):(this step may not needed if you use format and can see the new disk has partitions expected already)

root on testserver:/var/tmp # prtvtoc /dev/rdsk/c1t0d0s2 | fmthard -s - /dev/rdsk/c1t1d0s2

And use format -> partition to check the partitioning.

You can check device alias through eeprom:
root on testserver:/var/tmp # eeprom | grep devalias
nvramrc=devalias rootdisk /ssm@0,0/pci@18,700000/scsi@2/disk@0,0
devalias rootmirror /ssm@0,0/pci@18,700000/scsi@2/disk@1,0

To see mapping between physical device path and device name, use command format:
root on testserver:/var/tmp # format
0. c1t0d0 <SUN146G cyl 14087 alt 2 hd 24 sec 848>
1. c1t1d0 <SUN146G cyl 14087 alt 2 hd 24 sec 848>

At last, to clear corrupted submirror->reinit submirror->attach submirror:
metaclear d10 #may not needed if d10 is there after running metastat -i
metainit -f d10 1 1 c0t0d0s0 #may not needed if d10 is there after running metastat -i
metattach d0 d10 #to see the resync progress, run metastat -i|grep progress
metastat d0
metastat -p
metastat -i
metadb -i #if metadb is not on at least two physical disks, you may need create metadb on the new disk using  metadb -a -c 3 c0t0d0s7

Categories: Hardware, IT Architecture, Storage, Systems, Unix Tags:

alom/ilom/openboot prom commands help

January 11th, 2012 1 comment
1.Alom Available commands - This is help output from sun T2000 Alom(System Console)
Power and Reset control commands:
  powercycle [-y] [-f]
  poweroff [-y] [-f]
  poweron [-c] [FRU]
  reset [-y] [-c]
Console commands:
  break [-D] [-y] [-c]
  console [-f]
  consolehistory [-b lines|-e lines|-v] [-g lines] [boot|run]
Boot control commands:
  bootmode [normal|reset_nvram|bootscript="string"]
  setkeyswitch [-y] <normal|stby|diag|locked>
Locator LED commands:
  setlocator [on|off]
Status and Fault commands:
  clearfault <UUID>
  disablecomponent [asr-key]
  enablecomponent [asr-key]
  removefru [-y] <FRU>
  setfru -c [data]
  showcomponent [asr-key]
  showfaults [-v]
  showfru [-g lines] [-s|-d] [FRU]
  showlogs [-b lines|-e lines|-v] [-g lines] [-p logtype[r|p]]
  shownetwork [-v]
  showplatform [-v]
ALOM Configuration commands:
  setdate <[mmdd]HHMM | mmddHHMM[cc]yy][.SS]>
  setsc [param] [value]
  showhost [version]
  showsc [-v] [param]
ALOM Administrative commands:
  flashupdate <-s IPaddr -f pathname> [-v]
  help [command]
  resetsc [-y]
  restartssh [-y]
  setdefaults [-y] [-a]
  ssh-keygen [-l|-r] <-t {rsa|dsa}>
  showusers [-g lines]
  useradd <username>
  userdel [-y] <username>
  userpassword <username>
  userperm <username> [c][u][a][r]
  usershow [username]
2.ilom Available commands - This is help output from sun Fire E2900
addcodlicense      -- add a cod license
bootmode           -- configure the way Solaris boots at the next reboot
break              -- send break to the Solaris console
console            -- connect to the Solaris console
deletecodlicense   -- delete a cod license
disablecomponent   -- add a component to the blacklist
enablecomponent    -- remove a component from the blacklist
flashupdate        -- update firmware
forcepci           -- force pci mode
help               -- show help for a command or list of commands
history            -- show command history
inventory          -- show seprom contents of a FRU/system
logout             -- logout from this connection
password           -- set the system controller (LOM) access password
poweroff           -- power off system or components
poweron            -- power on system or components
reset              -- reset the Solaris system
resetsc            -- reset the system controller (LOM)
restartssh         -- restart SSH server (SSH must be enabled)
setalarm           -- set the alarm leds
setdate            -- set the date and time for the system
setescape          -- set system controller (LOM) escape sequence
seteventreporting  -- set event reporting
setlocator         -- set the system locator led
setls              -- set FRU location status
setupnetwork       -- setup system controller (LOM) network settings
setupsc            -- configure the system controller (LOM)
showalarm          -- show state of system alarms leds
showboards         -- show board information
showchs            -- show component health status
showcodlicense     -- show COD licenses
showcodusage       -- show COD resource usage
showcomponent      -- show state of a component
showdate           -- show the current date and time for the system
showenvironment    -- show environmental information
showerrorbuffer    -- show the contents of the error buffer
showescape         -- show system controller (LOM) escape sequence
showeventreporting -- show status of event reporting
showfault          -- show state of system fault led
showhostname       -- show hostname
showlocator        -- show state of system locator led
showlogs           -- show the logs
showmodel          -- show the platform model
shownetwork        -- show system controller (LOM) network settings and MAC addresses
showresetstate     -- show CPU registers after reset
showsc             -- show system controller (LOM) version and uptime
shutdown           -- shutdown solaris and take to standby mode
ssh-keygen         -- generate SSH host keys or show SSH host key fingerprint
testboard          -- test a CPU/Memory board
For oracle ilom:
stop -script -force /SYS #if stop /SYS won't work
start /HOST/console
reset -script -force /SP
start /SP/faultmgmt/shell  #and then you can do: fmadm faulty -a/fmadm repair
There are cases where the ilom hangs and needs to be restarted. Since the node is inaccessible, ipmitool will not work to reset the ilom so it must be done from a remote node as such:
ipmitool -H <ip address of problematic db node> -U root -P mypassword1 mc reset cold
Here's all the help message:

-> help
The help command is used to view information about commands and targets

Usage: help [-o|-output terse|verbose] [<command>|legal|targets|<target>|<target> <property>]

Special characters used in the help command are
[] encloses optional keywords or options
<> encloses a description of the keyword
(If <> is not present, an actual keyword is indicated)
| indicates a choice of keywords or options

help <target> displays description if this target and its properties
help <target> <property> displays description of this property of this target
help targets displays a list of targets
help legal displays the product legal notice

Commands are:

-> help reset
The reset command is used to reset a target.

Usage: reset [-script] [<target>]

Available options for this command:
-script : do not prompt for yes/no confirmation and act as if yes was specified

-> help targets

Target Meaning

/ Hierarchy Root
/HOST Host Information
/HOST/console Redirection of console stream to SP
/HOST/diag SP/HOST/diag Configuration #set /HOST/diag generate_host_nmi = true will panic the OS and save the core in current memory for support to analysis. It will immediately failover to other node but could take 15-30 mins to save big memory panic core. Before doing NMI(NonMaskable Interrupt) panic, spot any single disk with 100% busy from analytics tab. From our experience, it could be single bad disk hanging the bus and causes the issue. (From the Oracle ILOM web interface, click Host Management > Diagnostics, and then click Generate NMI.)

-> cd /HOST
-> show
        generate_host_nmi = (Cannot show property)
-> set generate_host_nmi=true
set ‘generate_host_nmi' to ‘true'

/HOST0/console Redirection of console stream to SP #start  /HOST0/console is like start /SP/console
/STORAGE Storage information
/STORAGE/raid Contains all RAID related information
/SYS Sensors, Indicators, and FRU Information #e.g. show/start/stop<-force>/reset /SYS, hard reset/reboot the server. show /SYS can see server type, serial number, power state. stop /SYS -h to print help message
/SP Service Processor
/SP/alertmgmt Alert rule management
/SP/alertmgmt/rules Alert rules node
/SP/cli Command line interface
/SP/clients Clients that connect to external services
/SP/clients/activedirectory Active Directory sub-directory
/SP/clients/activedirectory/admingroups administrator groups sub-directory
/SP/clients/activedirectory/alternateservers alternate servers sub-directory
/SP/clients/activedirectory/alternateservers/1/cert cert directory
/SP/clients/activedirectory/alternateservers/2/cert cert directory
/SP/clients/activedirectory/alternateservers/3/cert cert directory
/SP/clients/activedirectory/alternateservers/4/cert cert directory
/SP/clients/activedirectory/alternateservers/5/cert cert directory
/SP/clients/activedirectory/cert cert sub-directory
/SP/clients/activedirectory/customgroups custom groups sub-directory
/SP/clients/activedirectory/dnslocatorqueries DNS service record sub-directory
/SP/clients/activedirectory/opergroups operator groups sub-directory
/SP/clients/activedirectory/userdomains user domain sub-directory
/SP/clients/dns DNS resolution configuration
/SP/clients/ldap LDAP Client Properties
/SP/clients/ldapssl LDAP/SSL sub-directory
/SP/clients/ldapssl/admingroups administrator groups sub-directory
/SP/clients/ldapssl/alternateservers alternate servers sub-directory
/SP/clients/ldapssl/alternateservers/1/cert cert directory
/SP/clients/ldapssl/alternateservers/2/cert cert directory
/SP/clients/ldapssl/alternateservers/3/cert cert directory
/SP/clients/ldapssl/alternateservers/4/cert cert directory
/SP/clients/ldapssl/alternateservers/5/cert cert directory
/SP/clients/ldapssl/cert cert sub-directory
/SP/clients/ldapssl/customgroups custom groups sub-directory
/SP/clients/ldapssl/opergroups operator groups sub-directory
/SP/clients/ldapssl/optionalUserMapping userMapping(optional) sub-directory
/SP/clients/ldapssl/userdomains user domain sub-directory
/SP/clients/ntp NTP configuration
/SP/clients/ntp/server NTP server configuration
/SP/clients/radius RADIUS Client Properties
/SP/clients/smtp SMTP Server
/SP/clients/syslog Syslogd remote logging
/SP/clients/syslog/1 Syslogd remote logging server 1
/SP/clients/syslog/2 Syslogd remote logging server 2
/SP/clock Clock management #show /SP/clock/ datetime
/SP/config Config Backup / Restore settings
/SP/diag SP/Host Diagnositics Configuration
/SP/diag/snapshot Take snapshot of system for diagnostic purposes
/SP/faultmgmt FRUs with faults
/SP/faultmgmt/shell Fault management captive shell
/SP/firmware Firmware Base TARGET
/SP/logs Log events
/SP/logs/event Designations for event log
/SP/logs/event/list Designations for event log
/SP/network External network interface
/SP/network/interconnect USB Ethernet Submenu
/SP/network/ipv6 IPv6 Information
/SP/policy Policy Configuration
/SP/serial Serial interfaces
/SP/serial/external External serial interface
/SP/serial/host Host-to-SP serial interface
/SP/serial/portsharing Serial port sharing switch control
/SP/services Available services
/SP/services/http HTTP service
/SP/services/https HTTPS service
/SP/services/https/ssl HTTPS SSL Certficate Settings
/SP/services/https/ssl/custom_cert Custom SSL Certficate Settings
/SP/services/https/ssl/custom_key Custom SSL Private Key Settings
/SP/services/https/ssl/default_cert Default SSL Certficate Settings
/SP/services/ipmi Management of the IPMI service
/SP/services/kvms Management of the KVMS service
/SP/services/servicetag Servicetag configuration
/SP/services/snmp SNMP agent service configuration
/SP/services/snmp/communities snmp communities
/SP/services/snmp/users SNMP users
/SP/services/ssh Secure shell
/SP/services/ssh/keys Keys for secure shell
/SP/services/ssh/keys/dsa DSA key for secure shell
/SP/services/ssh/keys/rsa RSA key for secure shell
/SP/services/sso Single Sign-on Configuration
/SP/services/wsman Management of the WSMAN service
/SP/sessions Session description
/SP/users User description #e.g. show /SP/users/root and then check the "role" part

-> start /SP/faultmgmt/shell
Are you sure you want to start /SP/faultmgmt/shell (y/n)? y

faultmgmtsp> help

Built-in commands:
echo - Display information to user.
Typical use: echo $?
help - Produces this help.
Use 'help <command>' for more information about an external command.
exit - Exit this shell.

External commands:
fmadm - Administers the fault management service
fmdump - Displays contents of the fault and ereport/error logs
fmstat - Displays statistics on fault management operations
etcd - ereport injector

You can open another terminal in iLOM by the following steps:

First, click "Keyboard" -> "Left Alt Key". Then press F2. You'll get the terminal with "sh-3.2#". Then you should click again "Keyboard" -> "Left Alt Key" to release that control. You can now issue command like "fdisk" so that you can change partition's system id(Linux/SWAP/EFI GPT/VMware VMFS etc). If you want to turn back to the first console, just click "Keyboard" -> "Left Alt Key" and then press F1. (don't forget to uncheck "Left Alt key" after this)

3.KVM Available commands - This is help output from raritan kvm
?                 clear         connect
console_cmd       disconnect    exit
grep              help          list_interfaces
list_nodes        list_ports    listdevices
listinterfaces    listnodes     listports
ls                more          ssh
3.XSCF alom - this is help output about Fujitsu ilom

SCF> help
date Show date.
env-monitor Show system environment.
exit Exit XSCF Shell.
help Show help of shell command.
hangup Kill XSCF telnet connections.
lan-config Show LAN configuration.
logtest Save Test Log to check setting.
net-status Show SCF-LAN status.
nodeled Show and Control Check LED status.
por por,Power On Reset.
power-on Power on.
power-off Power off.
rci-config Show RCI configuration.
request Panic request.
send-break Send Break Signal to TTYA console.
set-console-device Set console device [serial | lan]
set-shell-command Change shell keyword.
show-access-logs Show the access logs.
show-config Show system configuration.
show-connections Show XSCF network connection status.(Telnet SSH)
show-console-device Show console device setting as TTYA Port.
show-console-logs Show console messages.
show-error-logs Show error logs.
show-event-logs Show event logs.
show-ipl-logs Show IPL,Initial Program Loading, messages.
show-mail-report Show Mail Report configuration.
show-panic-logs Show Panic messages.
show-power-logs Show power logs.
show-remcs Show REMCS configuration.
show-shell-command Show shell keyword.
show-status Show system error status.
shutdown Shutdown request.
thermal-history Show recorded thermal history.
version Show version.
who Who is on the XSCF system.
xir xir,eXternally Initiated Reset.


1.console -d 0. Also when you're in "SCF>", type "exit", you'll go back to console or OK mode.

2.type ~. to go back to XSCF

3.To log in Fujitsu console via SMC:

  • Login to DCM and find out the SMC for the partition
  • ssh as root to the SMC system
  • Find out the actual name of the partition name by viewing either /etc/hosts file or /etc/FJSVscstargets
  • Run the following command to get connected the partition console: /opt/FJSVcsl/bin/get_console -w -n <partition_name>
If you want to get into OK prompt of a Fujitsu partition:
  • ctrl+] to get the telnet prompt
  • From telnet prompt, type "send break"  to get OK prompt
  • to check xscf logs file fmdump -m, fmdump -v

4.Some HP-DL boxes have a DNS name called hostname-rib, you can do a nslookup -qt=all <hostname>, and then visit https://<dns> for a try. you can also have a try on https://<hostname>:2381 or telnet hostname_con for a try. Also, you can try ssh <hostname-rib> and then do a "start /SP/console" to the console access.

5.If the server is SUN Fire series, you may be interested in commands in /usr/platform/`uname -i`/sbin/{scadm, eeprom, fruadm, prtdiag, trapstat, wrsmconf, wrsmstat}

4.OpenBoot parameters and commands(this part is from url

About Openboot :
The firmware in Sun’s boot PROM is called OpenBoot. The main features of openboot are – initial program loading , & debugging features to assist kernel debugging. OpenBoot supports plug-in device drivers which are written in language Forth. This plug in feature allows Sun or any third-party vendors to develop new boot devices but without making any changes to boot PROM.

Accessing the openboot
Openboot console can be accessed by any of the following means . Be careful not to do this on a live system as you might end up in rebooting the server .

1. Rebooting a system , if auto-boot is not set to true rebooted system returns to OK> prompt which is openboot prompt

2. Pressing the keys L1 and A or STOP A , at the same time will bring you to the OpenBoot system. You will see the display
Type b (boot), c (continued), or n (new command mode)
Typing b boots the operating system . Typing c resumes the execution of a halted program. Typing n gets you to the Forth monitor, and the prompt will change to ok.

OpenBoot Parameters & commands

Following two tables gives a list of Openboot parameters & commands

Following two tables gives a list of
Openboot parameters & commands 
Display all variables and current
setenv <variable>  
Set variable to the given
set-default  <variable>  
Reset the value of variable
to the factory default.
Reset variable values to the factory
System directly boots without
stopping at OK> after power on.
command passed on to auto boot if true. 
File  for booting  Solaris , default is empty string .This
variable contains the default boot arguments that are used when
OpenBoot is not in diagnostic mode.
boot-device=disk net  
to boot from , multiple devices can be specified using spaces .Other
devices will be selected if  first device fails.


Tests the UTP  Ethernet port
link and flashes error messages if there is no network  link.
Use the system’s  MAC address
instead of network card’s MAC address . 
boot file for diagnostic mode This
variable contains the default diagnostic mode boot arguments.
booting device in diagnostic mode.
If true system runs in diagnostic
Level for diagnostics information , can 
be  min , max and minus . There
may be additional platform specific values. If set to off, POST is
not called. The default value is platform-dependent.
Input device used at power-on (
keyboard, ttya, or  ttyb).  
keyboard click sound
For custom keyboards
Output device used at power-on
ttya, or ttyb).
controls  the behavior of the
terminal emulator.
The value false causes  the terminal emulator to  stop
interpreting ANSI escape sequences resulting in  echoing them
to the output device.
Columns and Rows of display screen.


SCSI bus address of host adapter,
range 0-7. Used  in shared scsi storage envornment.
PS: If you want to change SCSI initiator ID on a PCI(Peripheral Component Interconnect) adapter/controller, you can refer to the following:
Order to probe pci and sbus
buses for devices.
If true , execute commands in
NVRAMRC during sys-
tem start-up. Defaults to false .
Displays contents of NVRAM
Firmware security level (options:
none, command ,
or full). If set to command or full, system will prompt for PROM
security password.
Security password setting when
security mode is command or full.
No. of bad security login .
password Set




this command shows the following
systems hardware information : Model, architecture, processor, keyboard, openboot
version, Serial no. Ethernet  address & host id.
test floppy – test floppy disk drive
test net - test network loop backs
test scsi – test scsi interface
test-all    test for all devices with self test
Show ticks of real-time clock
Monitor network broadcast packets
Monitor broadcast packets on all net
Show attached SCSI devices
Show attached SCSI devices for all
host adapters- internal & external.


boot – boot kernel from default
Factory default is to boot
from DISK if present, otherwise from NET.
boot net – boot kernel from network
boot cdrom – boot kernel from CD-ROM
boot disk1:h - boot from disk1 partition h
boot tape – boot default file from tape
disk myunix
 -as – boot myunix from disk with
flags "-as"
ok cd /pci@1f,4000/scsi@3 
ok .properties
ok ls
f00809d8 tape
f007ecdc disk
ok .speed
CPU Speed : 200.00MHz
UPA Speed : 100.00MHz 
PCI Bus A : 66Mhz
PCI Bus B : 33Mhz


commands at OK prompt.
nvedit Start
nvramrc line editor using a temporary edit buffer
use-nvramrc? If this variable is true , Contents of nvramrc is
executed automatically. Set using setenv command
nvrun Execute the contents of nvedit edit buffer
nvstore Save the contents of the nvedit buffer into NVRAM
nvrecover Recover nvramrc after a set-defaults
nvalias <name> <path> Edit nvramrc to include
devalias called ‘name’
nvunalias <name> Edit nvramrc to remove devalias called
Key Sequences
These commands are disabled if the PROM security is on. Also, if
your system has full security enabled, you cannot apply any of the
suggested commands unless you have the password to get to the ok
Stop – Bypass POST. This command does not depend on
security-mode. (Note: some systems bypass POST as a default; in
such cases, use Stop-D to
start POST.)
Stop-D -
Enter diagnostic mode (set diag-switch? to true).
Stop-F -
Enter Forth on TTYA instead of probing. Use exit to
continue with the initialization sequence. Useful if hardware is
Reset NVRAM contents to default values.
Categories: Hardware, Servers Tags:

ldap.conf and ldap_client_file not the same

January 2nd, 2012 No comments

You may find it weird that a ldap client has both ldap.conf and ldap_client_file, and the two files are referring to different ldap servers.

In short, this is because the default OpenLDAP client configuration file is located in /etc/ldap.conf, and on a typical Solaris LDAP client you will find a /var/ldap/ldap_client_file holding the information about which server(s) to contact and what authentication method to use. 

Here's more infomation:

Resolved – Device not ready, Logical unit not ready, manual intervention required

December 31st, 2011 No comments

Maybe you'll see error messages like:

end_request: I/O error, dev sdad, sector 0
sd 2:0:0:79: Device not ready: <6>: Current: sense key: Not Ready
Add. Sense: Logical unit not ready, manual intervention required

When you tried umount  and vxdg deport, there's still error messages like some volumes still in use etc, what you need do is:

1.vxdisk list to check the STD devices the dg are using.

2.syminq -pdevfile to check the STD device's BCV status.

3. wait till the sync complete and bcv device's status turns to Ready. you can umount/deport the vxdg and do other steps like rebackup etc.

Categories: Hardware, Storage Tags:

use ldapmodify to change ldap userpassword

December 23rd, 2011 1 comment

Want to change your ldap password(even more?) with ldapmodify? Here goes the steps:

1. Use  ldapsearch to get a glance at the account that needs password reset:

[root@doxer ~]# ldapsearch -LLL -b 'ou=people,dc=doxer,dc=org' -x -ZZ -H 'ldap://' -w 'password' -D 'cn=Manager,dc=doxer,dc=org' uid=liandy
dn: uid=liandy,ou=people,dc=doxer,dc=org
userPassword:: e1NTSEF9WGdafd3M4RjhuSSdadfdDVmTjAwN3B6cVlacjQ0N23/12/2011fag
shadowLastChange: 15347
gidNumber: 3000
uid: liandy
cn: liandy
homeDirectory: /home/liandy
objectClass: top
objectClass: account
objectClass: posixAccount
objectClass: shadowAccount
uidNumber: 250142da
gecos: liandy
loginShell: /bin/ksh
shadowFlag: 0

NB: -LLL here, you can refer to Here's the excerpt:

-LSearch results are display in LDAP Data Interchange Format detailed in ldif(5). A single -L restricts the output to LDIFv1. A second -L disables comments. A third -L disables printing of the LDIF version. The default is to use an extended version of LDIF.

2.Now let's use ldapmodify to change the password:

[root@doxer ~]ldapmodify -H 'ldap://' -D 'cn=Manager,dc=test,dc=com' -w 'password' -f /tmp/liandy.ldif
This is the content of /tmp/liandy.ldif
dn: uid=liandy,ou=people,dc=doxer,dc=org
changetype: modify

3.To confirm:

[root@doxer ~] ldapsearch -x -W -D 'cn=Manager,dc=test,dc=com'  -h 'ldap://' -b 'ou=people,dc=doxer,dc=org' cn=liandy modifytimestamp modifiersname

Now you can test the work by log on with new password!

NB: For more about ldapmodify, please refer to modification in one CMD etc.)

typical netbackup exclude_list usage

December 20th, 2011 No comments

bash-2.03$ cat /usr/openv/netbackup/exclude_list


Take *.[Aa][Rr][Cc] for example. it will exclude all the file suffix with .arc or .Arc ....


  1. Include lists can only include files and directories that are listed in the exclude lists so that they are not excluded.
  2. There's also a thread about include_list & exclude_list here

Linux hostname domainname dnsdomainname nisdomainname ypdomainname

December 20th, 2011 No comments

Here's just an excerpt from online man page of "domainname":

hostname - show or set the system's host name
domainname - show or set the system's NIS/YP domain name
dnsdomainname - show the system's DNS domain name
nisdomainname - show or set system's NIS/YP domain name
ypdomainname - show or set the system's NIS/YP domain name
hostname will print the name of the system as returned by the gethost-
name(2) function.

domainname, nisdomainname, ypdomainname will print the name of the sys-
tem as returned by the getdomainname(2) function. This is also known as
the YP/NIS domain name of the system.

dnsdomainname will print the domain part of the FQDN (Fully Qualified
Domain Name). The complete FQDN of the system is returned with hostname

Sometime you may find a weird thing that you can use ldap verification to log on a client, but you can not sudo to root. Now you should consider run domainname to check whether it's set to (none). If it does, you should consider set the domainname just using domainname command.

perl modules install and uninstall and list – using cpan

November 24th, 2011 No comments

If you want to install perl module SOAP::Lite using cpan for example, here's the command line:

perl -MCPAN -e 'install SOAP::Lite'

To test whether the module has been installed or not, run this:

perl -MSOAP::Lite -e "print \"Module installed.\\n\";"

Also, what about uninstallation?

Under windows:
if you have the activestate distro, go to shell/command prompt, enter PPM. When PPM opens type
"remove [package name]" this will uninstall that particular package for you. type "help remove" in PPM for more details.
Alternativly if you know what files came with the package, just delete them. Be aware that some modules will rely on other modules been installed so make sure there are no dependencies before you remove delete packages.

Under Linux:
depending on the module. (the path might be different on your system, check: perl -e 'print join("\n", @INC);' )
Also see:
Generally there is little reason to remove a module, probably why CPAN doesn't provide this function.

Oracle views – Static Data Dictionary Views & Dynamic Performance Views

November 5th, 2011 1 comment

Views are customized presentations of data in one or more tables or other views. You can think of them as stored queries. Views do not actually contain data, but instead derive their data from the tables upon which they are based. These tables are referred to as the base tables of the view.

Similar to tables, views can be queried, updated, inserted into, and deleted from, with some restrictions. All operations performed on a view actually affect the base tables of the view. Views can provide an additional level of security by restricting access to a predetermined set of rows and columns of a table. They can also hide data complexity and store complex queries.

Many important views are in the SYS schema. There are two types: static data dictionary views and dynamic performance views. Complete descriptions of the views in theSYS schema are in Oracle Database Reference.

Static Data Dictionary Views

The data dictionary views are called static views because they change infrequently, only when a change is made to the data dictionary. Examples of data dictionary changes include creating a new table or granting a privilege to a user.

Many data dictionary tables have three corresponding views:

  • DBA_ view displays all relevant information in the entire database. DBA_ views are intended only for administrators.An example of a DBA_ view is DBA_TABLESPACES, which contains one row for each tablespace in the database.
  • An ALL_ view displays all the information accessible to the current user, including information from the schema of the current user, and information from objects in other schemas, if the current user has access to those objects through privileges or roles.An example of an ALL_ view is ALL_TABLES, which contains one row for every table for which the user has object privileges.
  • USER_ view displays all the information from the schema of the current user. No special privileges are required to query these views.An example of a USER_ view is USER_TABLES, which contains one row for every table owned by the user.

The columns in the DBA_ALL_, and USER_ views are usually nearly identical.

Dynamic Performance Views

Dynamic performance views monitor ongoing database activity. They are available only to administrators. The names of dynamic performance views start with the characters V$. For this reason, these views are often referred to as V$ views.

An example of a V$ view is V$SGA, which returns the current sizes of various System Global Area (SGA) memory components.

Partitioned Tables and Indexes & Compressed Tables of oracle database

November 5th, 2011 No comments
1.Partitioned Tables and Indexes

You can partition tables and indexes. Partitioning helps to support very large tables and indexes by enabling you to divide the tables and indexes into smaller and more manageable pieces called partitions. SQL queries and DML statements do not have to be modified to access partitioned tables and indexes. Partitioning is transparent to the application.

After partitions are defined, certain operations become more efficient. For example, for some queries, the database can generate query results by accessing only a subset of partitions, rather than the entire table. This technique (called partition pruning) can provide order-of-magnitude gains in improved performance. In addition, data management operations can take place at the partition level, rather than on the entire table. This results in reduced times for operations such as data loads; index creation and rebuilding; and backup and recovery.

Each partition can be stored in its own tablespace, independent of other partitions. Because different tablespaces can be on different disks, this provides a table structure that can be better tuned for availability and performance. Storing partitions in different tablespaces on separate disks can also optimize available storage usage, because frequently accessed data can be placed on high-performance disks, and infrequently retrieved data can be placed on less expensive storage.

Partitioning is useful for many types of applications that manage large volumes of data. Online transaction processing (OLTP) systems often benefit from improvements in manageability and availability, while data warehousing systems benefit from increased performance and manageability.

As with tables, you can partition an index. In most situations, it is useful to partition an index when the associated table is partitioned, and to partition the index using the same partitioning scheme as the table. (For example, if the table is range-partitioned by sales date, then you create an index on sales date and partition the index using the same ranges as the table partitions.) This is known as a local partitioned index. However, you do not have to partition an index using the same partitioning scheme as its table. You can also create a nonpartitioned, or global, index on a partitioned table.

2.Compressed Tables

Table Compression is suitable for both OLTP applications and data warehousing applications. Compressed tables require less disk storage and result in improved query performance due to reduced I/O and buffer cache requirements. Compression is transparent to applications and incurs minimal overhead during bulk loading or regular DML operations such as INSERT, UPDATE or DELETE.

Extending tmpfs’ed /tmp on Solaris 10(and linux) without reboot

November 3rd, 2011 No comments

Thanks to Eugene.

If you need to extend /tmp that is using tmpfs on Solaris 10 global zone (works with zones too but needs adjustments) and don't want to undertake a reboot, here's a tried working solution.


echo "$(echo $(echo ::fsinfo | mdb -k | grep /tmp | head -1 | awk '{print $1}')::print vfs_t vfs_data \| ::print -ta struct tmount tm_anonmax | mdb -k | awk '{print $1}')/Z 0x20000" | mdb -kw

Note the 0x20000. This number means new size will be 1GB. It is calculated like this: as an example, 0x10000 in hex is 65535, or 64k. The size is set in pages, each page is 8k, so resulting allocation size is 64k * 8k = 512m. 0x20000 is 1GB, 0x40000 is 2GB etc.

If the server has zones, you will see more then one entry in ::fsinfo, and you need to feed exact struct address to mdb. This way you can change /tmp size for individual zones, but this can only be done from global zone.

Same approach can probably be applied to older Solaris releases but will definitely need adjustments. Oh, and in case you care, on Linux it's as simple as "mount -o remount,size=1G /tmp" :)


You may try "mount -t tmpfs -o size=7g shmfs /dev/shm" or "mount -t tmpfs -o size=7g tmpfs /dev/shm" on Linux platform.

Categories: IT Architecture, Kernel, Systems, Unix Tags:

why BST/DST(British Summer Time, Daylight Saving Time) achives the goal of saving energy

October 31st, 2011 No comments

Greenwich Mean Time

Tonight(30th October 2011), we'll welcome the GMT(Greenwich Mean Time) and hug away BST(British Summer Time, Daylight Saving Time) at 01:59:59 30th October 2011.

Why BST/DST(British Summer Time, Daylight Saving Time) achives the goal of saving energy? As you may think I still am going to work 8 hours a day and 365 days a year(may be too much? :D). OK, here's what I think.

As we all can experience, the sun arise earlier in Summer than in Autumn. So when you wake up in the morning, you'll do not need turn on the light, that does save the energy. And another extreme example, one man sleeps all the day and play games all the night, and another man sleeps all the night and work all the day, which one do you think is more environmentally friendly? Actually, this was why Benjamin Franklin, the man on $100, suggest DST(Daylight Saving Time).

Benjamin Franklin

Benjamin Franklin

Categories: Misc Tags:

List of build automation software

October 29th, 2011 No comments

Things like make/ant/hudson etc. See this url for details:

Categories: IT Architecture Tags:

vcs architecture overview

October 28th, 2011 No comments
vcs architecture overview

vcs architecture overview

Possible issue with latest version (6.8) of Oracle Explorer(vulnerability)

October 24th, 2011 No comments

I have been made aware of a potential issue with the latest version of explorer (6.8). The issue is caused because Explorer is calling a command (pcitool ) and that can cause a system to crash.
Check the version currently on your OS:
# cat /etc/opt/SUNWexplo/default/explorer|grep EXP_DEF_VERSION


Alternatively, if you want get it in a script:

VER=$(nawk  -F= '/EXP_DEF_VERSION/ {print $NF}' /etc/opt/SUNWexplo/default/explorer |sed 's/\"//g')

There are a number of workarounds...
1) downgrade explorer to 6.7

2) comment the line 674 ('get_cmd "/usr/sbin/pcitool -v" sysconfig/pcitool-v') by adding '#' to the beginning of it

3) make /usr/sbin/pcitool not executable on these systems (either remove it or change permissions)


For solaris explorer related concepts/download etc, please refer to

relationship between dmx srdf bcv

October 24th, 2011 No comments

The R1 BCV is related to the R1 DEV the R1 is srdf'd to the R2. The R2 is related to the R2 BCV. There is no direct relationship between the R1dev and the R2 bcv.
The symdg's as you know are contained in a local host based config database which group together devs you want to run commands on at the same time so you can fail them over a s a group or sync/split the bcv's as a group without having to list all the devs.





Because you only talk to the local array you specify your DEV's in your symdg as the ones that are local to you via symld. When symdgs are first created they are type R1 or R2 depending on if you're going to add R1 or R2 devices. This will automatically update when you fail over. The devices you add to your symdg are always the ones that are on your local array. The rdf relationship does not need to be specified in the symdg it is inherent to the device as it is a 1-2-1 relationship so when you run a symrdf query it will find out the paired device from the array.
BCV's are different because you can have more than one BCV attached to a device.
The –rdf in the symbcv command says bcv device <DEV> is remote i.e. is a bcv device on the remote array.
When you're running your commands then you have to picture yourself (well you don't but I do) standing locally on the host your running the commands on and think which devs appear local from there and which ones are remote.

Categories: Hardware, Storage Tags:

Three types of 301 rewrite/redirect for apache httpd server

October 4th, 2011 No comments

Type 1:Exact URL without any query parameters:
Type 2:Exact URL with any query parameters
Type 3:Exact URL plus query parameters and/or sub pages / EVERYTHING AFTER THIS INCLUDED

For Type 1:
RewriteRule ^/portal/site/doxerorg/mydoxer/anyone$ [L,R=301,NC]
For Type 2:
RewriteCond %{QUERY_STRING} ^(.*)$
RewriteRule ^/portal/site/doxerorg/mydoxer/mydoxer/anyone/register$ [R=301,L,NC]
For Type 3:
RewriteCond %{QUERY_STRING} ^(.*)$
RewriteRule ^/portal/site/doxerorg/mydoxer/article [R=301,L,NC]

1.In the destination URL, add '?' to the end if you don't want the query string to be auto-appended to the destination URL
2.[R] flag specifies a redirect, instead of the usual rewrite, [L] makes this the last rewrite rule to apply, [NC] means case insensitive

Categories: IT Architecture Tags:

Error extras/ata_id/ata_id.c:42:23: fatal error: linux/bsg.h: No such file or directory when compile LFS udev-166

September 21st, 2011 1 comment

For "Linux From Scratch - Version 6.8", on part "6.60. Udev-166", after configuration on udev, we need compile the package using make, but later, I met the error message like this:

"extras/ata_id/ata_id.c:42:23: fatal error: linux/bsg.h: No such file or directory"

After checking line 42 of ata_id.c under extras/ata_id of udev-166's source file, I can see that:

"#include <linux/bsg.h>"

As there's no bsg.h under $LFS/usr/include/linux, so I was sure that this error was caused by C header file loss. Checking with:
root:/sources/udev-166# /lib/
I can see that Glibc was 2.13, and GCC was 4.5.2:

GNU C Library stable release version 2.13, by Roland McGrath et al.
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
Compiled by GNU CC version 4.5.2.
Compiled on a Linux 2.6.22 system on 2011-09-04.
Available extensions:
crypt add-on version 2.1 by Michael Glad and others
GNU Libidn by Simon Josefsson
Native POSIX Threads Library by Ulrich Drepper et al
For bug reporting instructions, please see:

After some searching work on google, I can conclude that this was caused by GCC version. I was not going to rebuilt gcc for this, so I tried get this header file and put it under $LFS/usr/include/linux/bsg.h. You can go to to download the header file.

After copy & paster & chmod, I ran make again, and it succeeded.

Categories: IT Architecture, Kernel, Linux, Systems Tags:

Relationship between san’s HA DA FA RA WWN ZONE

September 15th, 2011 2 comments

Here's the image(Thanks to Peter G):


EMC Symmetrix connectivity to a host in a switched fabric logical and physical architecture

Here's another image of SAN architecture of EMC symmetrix arrays:







Or you may want to download the doc one:
Logicalandphysicalsanconnectivity.doc (1)

Categories: Hardware, Storage Tags:

Want your ldap password never expired? Here goes the howto

September 6th, 2011 2 comments

First, let's check when your password will expire using ldapsearch:
root on testserver:/tmp # ldapsearch -D cn="Directory Manager" -h -b ou=people,dc=testserver,dc=com uid=liandy passwordexpirationtime
Enter bind password:
version: 1
dn: uid=liandy,ou=people,dc=testserver,dc=com
passwordexpirationtime: 20111005230540Z

ldapsearch -D "cn='Directory Manager'" -h -b ou=people,dc=testserver,dc=com uid=liandy passwordexpirationtime #this should work also
Now, let's create a file named passwd.dn with content:
And the last step is to change the expiration time using ldapmodify:
root on testserver:/tmp # ldapmodify -D cn="Directory Manager" -h -f passwd.dn
Enter bind password:
modifying entry uid=liandy,ou=people,dc=testserver,dc=com
That's all the steps you need to change ldap password expiration time. To verify this has taken effect, fire ldapsearch to show expiration time just as the first step:
root on testserver:/tmp # ldapsearch -D cn="Directory Manager" -h -b ou=people,dc=testserver,dc=com uid=liandy passwordexpirationtime
Enter bind password:
version: 1
dn: uid=liandy,ou=people,dc=testserver,dc=com
passwordexpirationtime: 20120612135450Z
So you can see the ldap expiration time has been extended to 20120612.
If you want to change password for liandy on, do the following:
Create a file named passwd2.dn with content:
In passwd2.dn:

Then run ldapmodify to modify the password:
ldapmodify -D cn="Directory Manager" -h -f passwd2.dn

If you want to modify directory manager's password, here goes the step:
Create a file passwd3.dn with content:
dn: cn=config
changetype: modify
replace: nsslapd-rootpw
nsslapd-rootpw: EnterYourPassword

Then run ldapmodify to change the password:
ldapmodify -D "cn=directory manager" -h -f passwd3.dn

If you forget the password for directory manager, you then need firstly find dse.ldap under ldap/slapd-Portal1/config, then encrypt your password, then modify nsslapd-rootpw.

Categories: IT Architecture, Linux, Systems, Unix Tags:

hp openview monitoring solution – enable disable policies

August 18th, 2011 2 comments

This document is part of the “ESM – How To” Guides and gives instructions on how to Disable and Enable monitoring policies on Servers managed by Openview for Unix (OVOU), Openview for Windows (OVOW) and opsview for blackout or maintenance purposes.

Monitoring disabling / enabling process may differ depending what solution is used for monitoring the servers involved in the DR test.

This document list procedures to disable and enable monitoring in different monitoring solutions.

1.Monitoring changes to servers monitored in OVOU(Unix/Linux)
1.1. Disabling monitoring templates
Disable monitoring templates on the monitored server.
Logon to server and execute following command as root user
/opt/OV/bin/opctemplate –d -all

Above command will disable all monitoring policies on the server.

Now disable openview agent heartbeat polling from Openview servers(Server Side):
Execute following commands to disable OVO agent heartbeat polling
/opt/OV/bin/OpC/opchbp –stop <name of server>

1.2. Enabling monitoring templates
Enable monitoring templates on the monitored server.
Logon to server and execute following command as root user
/opt/OV/bin/opctemplate –e -all

Above command will enable all monitoring policies on the server.

Now enable openview agent heartbeat polling from Openview servers(Server Side):
Execute following commands to enable OVO agent heartbeat polling
/opt/OV/bin/OpC/opchbp –start <name of server>

2.Disabling monitoring for servers monitored in OVOW(Windows)
Firstly, access the Web Console of OV:

2.1 Disabling policy(s)
Select the Policies Icon on the left hand panel and then expand the Nodes by selecting the select the plus next to the nodes in the center panel. Once you have located the server that you want to disable policies on select it and the policy inventory is shown in the right hand panel. The policies to be disabled are selected using the check boxes next to the policy name, or to disable all the policies select the check box next to the name, and this will select all the policies. Then select the Disable tab and the policies will be disabled, the display will show Active and pending until all the policies have been disabled, use the Refresh tab to update the screen.

2.2 Enabling policy(s)
Please refer to 2.1 Disabling policy(s)

3.Monitoring changes for servers monitored in Opsview(Nagios)
Log on opsview through web, search and locate the host you want operate on, Click on the grey arrow on the right side of the node and choose “Schedule downtime”. Now you can choose the start and End time for the downtime for this server.

obu firmware patching for sun T2000/T5120/T5220 servers OBP patching

August 17th, 2011 No comments

Don't know why there's some formatting errors with this article, you can download the PDF version here: obu firmware patching for sun T2000-T5120-T5220 servers OBP patching

You can download Sun_System_Firmware-6_7_11-Sun_Fire_T2000 from or here(For SunFireT2000)

Categories: Hardware, Servers Tags:

hpux san storage configure howto steps for veritas vxvm

August 15th, 2011 No comments

1/             Run  ioscan -fnkC disk  & dump to a file

2/            run ioscan no options and dump to a file

3/            run ioscan -fnkC disk  and check for disk

devices that are not claimed.

4/            run  insf -ev to allocated the new entries to /dev/dsk/xxxxx

5/            vxdisksetup  / vxdiskadm to setup disks

6/           vxdctl enable

7/            vxvm - add disks to dg etc

Categories: Hardware, Storage Tags:

Emcgrab download url

July 27th, 2011 1 comment

Just go to to select yours and download(solaris, linux, aix etc.). The latest version is emcgrab-4.4.4.


emcgrab is also known as Remediation HEAT report. EMC grab report generates file that EMC or storage team might use for diagnostics and monitoring of storage usage by the client and possible issues; it also dumps logs/config into this file. This procedure proved to be safe, but need to be done out of hours if that`s possible.

correctable ecc event detected by cpu0/1/3/4

July 20th, 2011 No comments

If you receive these kinds of alerts in Solaris, it means your server has Memory Dimm issue. Please check with hrdconf/madmin(HP-UX) or prtconf(SUN solaris) to see the error message.

For more information about ECC memory, you can refer to the following article:

convert squid access.log time to human-readable format

July 13th, 2011 1 comment

If you're looking at squid access.log, you'll find the first column of it is the time, for example:
1310313302.640 829 TCP_MISS/200 104 CONNECT - DIRECT/ -
1310313303.484 1845 TCP_MISS/200 104 CONNECT - DIRECT/ -
This is not very human readable. Now we can use perl to convert squid access.log time to human-readable format, just one line command:

cat /var/log/squid/access.log |perl -nwe's/^(\d+)/localtime($1)/e; print'

After this, it'll look like this:
Sun Jul 10 09:55:03 2011.484 1845 TCP_MISS/200 104 CONNECT - DIRECT/ -
Sun Jul 10 09:55:07 2011.146 355 TCP_MISS/200 1176 GET - DIRECT/ text/html
Hey, more human-readable, right?

Resolved – httpd: fatal: open failed: No such file or directory

July 9th, 2011 No comments

When I tried to start up IBM http server on my Solaris, I met this error message: httpd: fatal: open failed: No such file or directory
This error was caused by library can not be found in the current library path environment variable. We should add /apps/IBMHTTPD/Installs/IHS61-01/lib to LD_LIBRARY_PATH to make be seen by ld.
Here goes the resolution:
#export LD_LIBRARY_PATH=/apps/IBMHTTPD/Installs/IHS61-01/lib:$LD_LIBRARY_PATH #set environment variable
#/apps/IBMHTTPD/Installs/IHS61-01/bin/httpd -d /apps/IBMHTTPD/Installs/IHS61-01 -d /apps/IBMHTTPD/Installs/IHS61-01 -f /apps/IBMHTTPD/Installs/IHS61-01/conf/ihs.conf -k restart #restart IHS
#/usr/ucb/ps auxww|grep -i ibmhttpd #check the result


Here's more about (from book <Optimizing Linux Performance: A Hands-On Guide to Linux Performance Tools>)

When a dynamically linked application is executed, the Linux loader,, runs loads all the application’s libraries and connects symbols that the application uses with the functions the libraries provide. Because different libraries were originally linked at different and possibly overlapping places in memory, the linker needs to sort through all the symbols and make sure that each lives at a different place in memory. When a symbol is moved from one virtual address to another, this is called a relocation. It takes time for the loader to do this, and it is much better if it does not need to be done at all. The prelink application aims to do that by rearranging the system libraries of the entire systems so that they do not overlap. An application with a high number of relocations may not have been prelinked.

The Linux loader usually runs without any intervention from the user, and by just executing a dynamic program, it is run automatically. Although the execution of the loader is hidden from the user, it still takes time to run and can potentially slow down an application’s startup time. When you ask for loader statistics, the loader shows the amount of work it is doing and enables you to figure out whether it is a bottleneck.

The ld command is invisibly run for every Linux application that uses shared libraries. By setting the appropriate environment variables, we can ask it to dump information about its execution. The following invocation influences ld execution:
env LD_DEBUG=statistics,help LD_DEBUG_OUTPUT=filename <command>