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I am not able to start MySQL, on a CentOS 6 system. When I checked in the mysqllog the error I get is

121117 11:16:19 [ERROR] /usr/libexec/mysqld: Error writing file '/var/run/mysqld/' (Errcode: 28) 
121117 11:16:19 [ERROR] Can't start server: can't create PID file: No space left on device 
121117 11:16:19 mysqld_safe Number of processes running now: 0

I ran a df -h command and if I am not wrong, /var/ disc usage is 4% only.

/dev/sda6              16G   15G     0 100% /
tmpfs                 3.9G     0  3.9G   0% /dev/shm
/dev/sda1             194M   51M  134M  28% /boot
/dev/sda3            1008M  284M  674M  30% /tmp
/dev/sda5            1008M   34M  924M   4% /var/tmp
/dev/sdb1              79G  184M   75G   1% /mnt/vol1
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up vote 0 down vote accepted

Your /var/tmp partition is at 4%

Your /var folder will be under the / root partition which is at 100%

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so andrew what can i do to resolve this. Till yesterday it was working fine. I am new to linux based systems – Raghunath Nov 17 '12 at 7:51
The usual hog is /var/log - purge some of the old logs (and setup logrotate if you aren't already using it). Are you SysAdmin? If not, talk to the SysAdmin – Andrew Nov 17 '12 at 7:59

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