Nagios Support Forum

We were able to upgrade to NagiosXI 2014R1.3, all works fine for existing hosts and services, but if I edit a service or add a new host with services, then the services keeps flapping:

2014-07-19 09:36:47 XXX UP HARD 1 of 5 HTTP OK: HTTP/1.1 200 OK - 79826 bytes in 0.046 second response time
2014-07-19 09:35:56 XXX DOWN HARD 1 of 5 CRITICAL - Network Unreachable (localhost)
2014-07-19 09:31:47 XXX UP HARD 1 of 5 HTTP OK: HTTP/1.1 200 OK - 79826 bytes in 0.047 second response time
2014-07-19 09:30:16 XXX DOWN HARD 1 of 5 CRITICAL - Network Unreachable (localhost)

The nagios node has IPv4 + IPv6 connectivity, but, the checked hosts do not have quad A records. It seems it's doing an IPv6 lookup first and then an IPv4 lookup, but it sends out an alert (which it shouldn't, nothing is down).

How can I force NagiosXI to only use IPv4? Or better yet, not to send out an error when the host only has IPv4, but NagiosXI has IPv4+IPv6.

thanks!

You can pass "-4" flag to your command to force it to use ipv4 only. See the plugins usage:

Thanks, yes, I did that, but there's no IPv6 on the server, nor any quad A for the zone, so why is it trying IPv6? It shouldn't be doing that.

Either way, it's working now.

It should not try ipv6 first unless it is available. I bet your server is configured to support ipv6 and for some reason the plugin tries that first even though you do not have a valid interface up running ipv6. I just tested on one of my test boxes and didn't experience the issue, so this may be unique to your env.

abrist wrote:It should not try ipv6 first unless it is available. I bet your server is configured to support ipv6 and for some reason the plugin tries that first even though you do not have a valid interface up running ipv6. I just tested on one of my test boxes and didn't experience the issue, so this may be unique to your env.

IPv6 is explicitly disabled, no local either. It only happens for hosts that were in nagios pre upgrade; new ones work fine (but there's too many for me to re-enter all of them).

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1

hmmm, Only for ping checks? Did the commands change? Have you ever altered the default ping/host_alive/icmp commands in the ccm?

Yes, ping only; there was a different issue with the host check, but that seemed to be a syntax difference which was solved by just forcing the configs to be rewritten. No, I only altered the command now to add the -4 flag.

Either way, that works for now and I'll remove and re-add the existing hosts slowly over time.

Safe to lock this thread up?