multipathd -k results in ux_socket_connect error

On Red Hat Enterprise Linux 5 (RHEL 5), when trying to enter the multipathd shell using multipathd -k, I ran into the following error:

ux_socket_connect: No such file or directory

Because running multipath -ll generated the desired output I assumed (and we all know what assuming does!) and began Googling a solution... and it turned out multipathd was not actually running or even set to start on boot. Solution:

chkconfig multipathd on
service multipathd start
multipathd -k

Lesson learned.

Cron not working for normal user

Recently I ran into an interesting "issue" where a user's cron job wouldn't work and restarting the cron daemon did no good. Having checked the /etc/cron.allow and /etc/cron.deny files, I found nothing relevant, and so I Googled the error found in /var/log/messages:

Apr  9 12:31:01 server crond[8993]: Authentication token is no longer valid; new one required.

No password was necessary for this account, so to the system, it was a "locked" account, whereas to me, it was a service account.

[root@server ~]# grep username /etc/shadow
username:!!:13306:0:90:14:::

 Setting a password resolved this.

MaxRequestLen

The following error:

[Sat Jun 11 14:33:51 2011] [warn] [client 98.30.32.199] mod_fcgid: HTTP request length 131533 (so far) exceeds MaxRequestLen (131072)

Requires a review of the FcgidMaxRequestLen or MaxRequestLen parameter:

http://httpd.apache.org/mod_fcgid/mod/mod_fcgid.html#fcgidmaxrequestlen

Fix: set value (in bytes) for FcgidMaxRequestLen inside httpd.conf or apache2.conf.