ip_conntrack: table full, dropping packet

If you ever see the following error in the 'dmesg' or '/var/log/messages' log files, it means the server is dropping packets and will look like a network issue.

~~~~~~
printk: 167 messages suppressed.
ip_conntrack: table full, dropping packet.
~~~~~~

This error has to do with the value in '/proc/sys/net/ipv4/ip_conntrack_max' set to low, and letting the system only handle a few connections at once. This value is usually imposed when APF is installed, and the following should be done to correct it:

root@server[~]# echo "138304" > /proc/sys/net/ipv4/ip_conntrack_max

add the following to /etc/sysctl.conf:

sys.net.ipv4.ip_conntrack_max = 138304

If you are running APF, modify the following line to:

SYSCTL_CONNTRACK="138304"

To check what the current value is you can use:

root@server[~]# cat /proc/sys/net/ipv4/ip_conntrack_max

Thank you.


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