RHCS6: Basic operations on clustered services

RHCS: Basic operations on clustered services

# Tested on RHEL 6

# On a cluster like following one:

root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:39:54 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                      mynodeA    started
 service:myservice-3                                      mynodeB    started



# Stop a service ('-d' for "disable")
# ------------------------------------------------------------------------------------------

root@mynodeA:/#> clusvcadm -d myservice-2

root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:40:22 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                     (mynodeA)   disabled
 service:myservice-3                                      mynodeB    started



# Start a stopped service ('-e' for "enable")
# ------------------------------------------------------------------------------------------

# To be able to start a service it has to be in 'disabled' status. Sometimes the service
# may be in 'failed' status (neither 'started' nor 'disabled'), what means that there has
# been a problem with the service. In those cases, after solving the problems that
# potentially prevent the service from starting, we should run once again stop command,
# "clusvcadm -d" on the service in order to pass it to 'disabled' status.

# Obviously, when starting a service, we have to indicate on which node we want to start
# it ('-m' parameter)

root@mynodeA:/#> clusvcadm -e myservice-2 -m mynodeB

root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:45:17 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                      mynodeB    started
 service:myservice-3                                      mynodeB    started

# If service was in 'failed' status, first pass it to 'disabled'

root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:43:21 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                     (mynodeA)   failed
 service:myservice-3                                      mynodeB    started


root@mynodeA:/#> clusvcadm -d myservice-2


root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:44:01 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                     (mynodeA)   disabled
 service:myservice-3                                      mynodeB    started



# Switch a service to a different node ('-r' for "relocate")
# ------------------------------------------------------------------------------------------

# When starting a service, we have to indicate on which node we want to start
# it ('-r' parameter)


root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:45:17 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                      mynodeB    started
 service:myservice-3                                      mynodeB    started


root@mynodeA:/#> clusvcadm -r myservice-2 -m mynodeA


root@mynodeA:/#> clustat
Cluster Status for mycluster @ Thu Sep 25 21:49:29 2014
Member Status: Quorate

 Member Name                                          ID   Status
 ------ ----                                         ---- ------
 mynodeA                                               1  Online, Local, rgmanager
 mynodeB                                               2  Online, rgmanager

 Service Name                                         Owner (Last)   State
 ------- ----                                         ----- ------   -----
 service:myservice-1                                      mynodeA    started
 service:myservice-2                                      mynodeA    started
 service:myservice-3                                      mynodeB    started
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