Monthly Archives: July 2018

Restart slave thread in MySQL when specific error occurred

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On one of slaves I got error:

write failed: No space left on device (28)

I also found that slave got 1062 error (“Duplicate entry”) and stopped. I cleaned up some free space (old logs). When I tried to restart it with pt-slave-restart then I found that IO_Thread downloads binlogs from master and uses all free space again.

As a workaround – I decide to start just SQL_Thread, let it process all relay logs and then start IO_Thread again.

This is quick bash oneliner I created, which checks replication and if 1062 error exists then does skipping and starting SQL_Thread again.

while true; do if [[ $(mysql -e "show slave status\G" | grep "Last_SQL_Errno: 1062" -c) -gt 0 ]]; then mysql -e "set global sql_slave_skip_counter=1; start slave sql_thread;"; fi; done

This was enough to get issue fixed.

How to clear all iptables rules and allow everything

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How to clear all iptables rules and allow everything

iptables -F
iptables -X
iptables -t nat -F
iptables -t nat -X
iptables -t mangle -F
iptables -t mangle -X
iptables -P INPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -P OUTPUT ACCEPT