> -----Original Message----- > From: linux-cluster-bounces@xxxxxxxxxx [mailto:linux-cluster-bounces@xxxxxxxxxx] > On Behalf Of Jason Fitzpatrick > Sent: Tuesday, June 22, 2010 4:40 AM > To: Kit Gerrits > Cc: linux clustering > Subject: Re: Basic Active Active File Server > > Hi Kit.. > > Awesome and all as I am when it comes to computers, networking is a > serious weak point ;0) > > How would I go about checking if multicast traffic is making it > between the two nodes, ... When I suspect multicast problems I like to do a sanity check with multicast ping. First, on all cluster hosts make sure you enable ICMP multicast responses: echo 0 >/proc/sys/net/ipv4/icmp_echo_ignore_broadcasts Second, find your multicast address on a cluster node. This is shown by "cman_tool status" or "ip maddr": # ip maddr 1: lo inet 224.0.0.1 2: eth0 link 01:00:5e:00:00:01 inet 224.0.0.1 3: eth1 link 01:00:5e:40:f9:ce link 01:00:5e:00:00:01 inet 239.192.249.206 <---- my multicast address inet 224.0.0.1 Noting the address and interface name above, try a multicast ping with a count of at least 2: # ping -I eth1 -b -L 239.192.249.206 -c 2 PING 239.192.249.206 (239.192.249.206) from 10.65.3.166 eth1: 56(84) bytes of data. 64 bytes from 10.65.3.102: icmp_seq=1 ttl=64 time=0.394 ms 64 bytes from 10.65.3.86: icmp_seq=1 ttl=64 time=0.415 ms (DUP!) 64 bytes from 10.65.3.182: icmp_seq=1 ttl=64 time=0.418 ms (DUP!) 64 bytes from 10.65.3.134: icmp_seq=1 ttl=64 time=0.420 ms (DUP!) 64 bytes from 10.65.3.87: icmp_seq=1 ttl=64 time=0.971 ms (DUP!) 64 bytes from 10.65.3.183: icmp_seq=1 ttl=64 time=0.985 ms (DUP!) 64 bytes from 10.65.3.103: icmp_seq=1 ttl=64 time=0.987 ms (DUP!) 64 bytes from 10.65.3.167: icmp_seq=1 ttl=64 time=0.990 ms (DUP!) 64 bytes from 10.65.3.135: icmp_seq=1 ttl=64 time=0.992 ms (DUP!) 64 bytes from 10.65.3.134: icmp_seq=2 ttl=64 time=0.486 ms 9 ping responses on a cluster of size 10. Looks good. Repeat this test on each cluster member--you should see a consistent number of replies. -Jeff -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
