resolved – check backend OHS httpd servers for BIG ip F5 LTM VIP

May 23rd, 2014

Assume you want to check the OHS or httpd servers one LTM VIP example.vip.com is routing traffic to. Then here's the steps:

  1. get the ip address of VIP example.vip.com;
  2. log on LTM's BUI. Local traffic-> virtual servers -> virtual server list, search ip
  3. click "edit" below column "resource"
  4. note down default pool
  5. search pool name in local traffic -> virtual servers -> pools -> pool list
  6. click the number below column members. Then you'll find the OHS servers and ports the VIP will route traffic to.

test telnet from VLAN on cisco router device

May 22nd, 2014

If you want to test telnet connection from one vlan to specific destination IP, here is the howto:

test-router# telnet 10.200.244.14 80 source vlan 125
Trying 10.200.244.14...
Connected to 10.200.244.14.
Escape character is '^]'.

Good luck.

Resolved – input_userauth_request: invalid user root

May 15th, 2014

Today when I tried to ssh to one linux box but it failed, and /var/log/secure gave the following messages:

May 15 04:05:07 testbox sshd[22925]: User root from 10.120.120.188 not allowed because not listed in AllowUsers
May 15 04:05:07 testbox sshd[22928]: input_userauth_request: invalid user root
May 15 04:05:07 testbox unix_chkpwd[22929]: password check failed for user (root)
May 15 04:05:07 testbox sshd[22925]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=10.120.120.188 user=root
May 15 04:05:09 testbox sshd[22925]: Failed password for invalid user root from 10.120.120.188 port 50362 ssh2
May 15 04:05:10 testbox unix_chkpwd[22930]: password check failed for user (root)
May 15 04:05:11 testbox sshd[22928]: Connection closed by 10.120.120.188

Then I had a check of /etc/ssh/sshd_config and modified the following:

[root@testbox ~]# egrep 'PermitRoot|AllowUser' /etc/ssh/sshd_config
PermitRootLogin yes #change this to yes
#AllowUsers testuser #comment out this

Later, restart sshd, service sshd restart, and later ssh worked.

Categories: IT Architecture, Linux, Systems Tags: ,

resolved – fsinfo ERROR: Stale NFS file handle POST

May 15th, 2014

Today when I tried mount NFS share from one NFS server, it timeout with "mount.nfs: Connection timed out".

I tried to search something in /var/log/messages but no useful info there was found. So I used tcpdump on NFS client:

[root@dcs-hm1-qa132 ~]# tcpdump -nn -vvv host 10.120.33.90 #server is 10.120.33.90, client is 10.120.33.130
23:49:11.598407 IP (tos 0x0, ttl 64, id 26179, offset 0, flags [DF], proto TCP (6), length 96)
10.120.33.130.1649240682 > 10.120.33.90.2049: 40 null
23:49:11.598741 IP (tos 0x0, ttl 62, id 61186, offset 0, flags [DF], proto TCP (6), length 80)
10.120.33.90.2049 > 10.120.33.130.1649240682: reply ok 24 null
23:49:11.598812 IP (tos 0x0, ttl 64, id 26180, offset 0, flags [DF], proto TCP (6), length 148)
10.120.33.130.1666017898 > 10.120.33.90.2049: 92 fsinfo fh Unknown/0100010000000000000000000000000000000000000000000000000000000000
23:49:11.599176 IP (tos 0x0, ttl 62, id 61187, offset 0, flags [DF], proto TCP (6), length 88)
10.120.33.90.2049 > 10.120.33.130.1666017898: reply ok 32 fsinfo ERROR: Stale NFS file handle POST:
23:49:11.599254 IP (tos 0x0, ttl 64, id 26181, offset 0, flags [DF], proto TCP (6), length 148)
10.120.33.130.1682795114 > 10.120.33.90.2049: 92 fsinfo fh Unknown/010001000000000000002FFF000002580000012C0007B0C00000000A00000000
23:49:11.599627 IP (tos 0x0, ttl 62, id 61188, offset 0, flags [DF], proto TCP (6), length 88)
10.120.33.90.2049 > 10.120.33.130.1682795114: reply ok 32 fsinfo ERROR: Stale NFS file handle POST:

The reason of "ERROR: Stale NFS file handle POST" may caused by the following reasons:

1.The NFS server is no longer available
2.Something in the network is blocking
3.In a cluster during failover of NFS resource the major & minor numbers on the secondary server taking over is different from that of the primary.

To resolve the issue, you can try bounce NFS service on NFS server using /etc/init.d/nfs restart.

Categories: Hardware, NAS, Storage Tags:

resolved – show kitchen sink buttons when wordpress goes to fullscreen mode

April 11th, 2014

When you click the full-screen button of wordpress TinyMCE, wordpress will go to "Distraction-Free Writing mode", which benefits as the name suggests. However, you'll also find the toolbox of TinyMCE will only show a limited number of buttons and the second line of the toolbox(kitchen sink) will not show at all(I tried install plugin such as ultimate TinyMCE or advanced TinyMCE, but the issue remained):

full-screenPreviously, you can type ALT+SHIFT+G to go to another type of fullscreen mode, which has all buttons include kitchen sink ones. However, seems now the updated version of wordpress has disabled this feature.

To resolve this issue, we can insert the following code in functions.php of your theme:

function my_mce_fullscreen($buttons) {
$buttons[] = 'fullscreen';
return $buttons;
}
add_filter('mce_buttons', 'my_mce_fullscreen');

Later, the TinyMCE will have two full-screen button:

full-screen buttonsMake sure to click the SECOND full-screen button. When you do so, the editor will transform to the following appearance:

full-screen with kitchen sinkI assume this is what you're trying for, right?

 

 

Categories: Misc Tags:

add horizontal line button in wordpress

April 11th, 2014

There're three methods for you to add a horizontal line button in wordpress:

Firstly, switch to "Text" mode, and enters <hr />.

Secondly, add the following in functions.php of your wordpress theme:

function enable_more_buttons($buttons) {
$buttons[] = 'hr';
return $buttons;
}
add_filter("mce_buttons", "enable_more_buttons");

horizontal line

Thirdly, you can install plugin "Ultimate TinyMCE", and in its setting, you can enable horizontal line button there in one click! This is my recommendation.

ultimate tinymce

Categories: Misc Tags: ,