Troubleshoot Load Balancers

Use the tips give below to troubleshoot the LVS Load Balancer:

• Use the command shown below to find the syslogs related to the Keepalived: 

  $tail -f /var/log/syslog

• Check the configured VIP addresses for eth0 using the ip addr list command. 
  Example output:

  1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
  	link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  	inet 127.0.0.1/8 scope host lo
     	valid_lft forever preferred_lft forever
  	inet6 ::1/128 scope host
     	valid_lft forever preferred_lft forever
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
  	link/ether fa:16:3e:d3:09:4a brd ff:ff:ff:ff:ff:ff
  	inet 192.168.30.24/24 brd 192.168.30.255 scope global eth0
     	valid_lft forever preferred_lft forever
  	inet 192.168.30.30/32 scope global eth0
     	valid_lft forever preferred_lft forever
  	inet6 fe80::f816:3eff:fed3:94a/64 scope link
     	valid_lft forever preferred_lft forever
  

• If you are unable to connect to the server, you can telnet to the VIP and port.

  During failover, it is normal to expect a delay in the new connection establishment, until the slave node takes control. The delay depends on the load, on the cluster. Therefore it will take several minutes.

  $telnet 192.168.30.30 8080

  If telnet reports no route to host, recheck the keepalived.conf  configuration file, which is in the the <KEEPALIVEID_HOME> /etc/keepalived directory to make sure that you have entered the correct VIP and RIPs.