RHCS: Could not connect to resource group manager - macau23/low_visibility_solutions GitHub Wiki

Problem: In RHCS (Red Hat Cluster Suite), rgmanager appears to start, but does not work. Running strace shows a missing file:

# /etc/init.d/rgmanager start
Starting Cluster Service Manager: [ OK ]

# /etc/init.d/rgmanager status
rgmanager is stopped

# strace clusvcadm -e someservice
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4672fb1000
write(1, "Local machine trying to enable s"..., 44Local machine trying to enable service:someservice...) = 44
socket(PF_FILE, SOCK_STREAM, 0) = 5
connect(5, {sa_family=AF_FILE, path="/var/run/cluster/rgmanager.sk"}, 110) = -1 ENOENT (No such file or directory)
close(5) = 0
write(1, "Could not connect to resource gr"..., 44Could not connect to resource group manager
) = 44
exit_group(1)

Solution:

The missing file is a red herring. In this example multicast was the problem: it was not enabled on the network.

There are two solutions:

Enable multicast
Use unicast in both cluster.conf AND openais.conf, e.g.

/etc/cluster/cluster.conf:
..
  <cman expected_votes="2" transport="udpu"/>
..

/etc/ais/openais.conf:
..
        interface {
                ringnumber: 0
                bindnetaddr: 10.254.5.0
                broadcast: yes
        }
..