"A RMC network connection to the partition is not present. Verify the network settings on the partition and the HMC. If you select OK you will have to restart the partition for the resource changes to take effect."

Did you ever got this alert when you were trying to run some DLPAR operations? It can be fixed very easily (more or less). Please follow.

1. restart rsct and rsct_rm groups, wait a minute or so and try again. If it works, you are done. If not, go to point 2.

gzaix@root:/home/root # lssrc -g rsct 
Subsystem         Group            PID          Status  
 ctrmc            rsct             1028156      active
 ctcas            rsct                          inoperative
gzaix@root:/home/root # [b]stopsrc -g rsct[/b] 
0513-044 The ctrmc Subsystem was requested to stop.
gzaix@root:/home/root # lssrc -g rsct  
Subsystem         Group            PID          Status 
 ctcas            rsct                          inoperative
 ctrmc            rsct                          inoperative
gzaix@root:/home/root # [b]startsrc -g rsct[/b]
0513-059 The ctcas Subsystem has been started. Subsystem PID is 11706538.
0513-059 The ctrmc Subsystem has been started. Subsystem PID is 13627430.
gzaix@root:/home/root # lssrc -g rsct      
Subsystem         Group            PID          Status 
 ctcas            rsct             11706538     active
 ctrmc            rsct             13627430     active

gzaix@root:/home/root # lssrc -g rsct_rm
Subsystem         Group            PID          Status 
 IBM.CSMAgentRM   rsct_rm          999456       active
 IBM.ServiceRM    rsct_rm          1077284      active
 IBM.DRM          rsct_rm          1101894      active
 IBM.AuditRM      rsct_rm                       inoperative
 IBM.ERRM         rsct_rm                       inoperative
 IBM.HostRM       rsct_rm                       inoperative
 IBM.LPRM         rsct_rm                       inoperative
gzaix@root:/home/root # [b]stopsrc -g rsct_rm[/b]
0513-044 The IBM.CSMAgentRM Subsystem was requested to stop.
0513-044 The IBM.ServiceRM Subsystem was requested to stop.
0513-044 The IBM.DRM Subsystem was requested to stop.
gzaix@root:/home/root # [b]startsrc -g rsct_rm[/b]
0513-059 The IBM.CSMAgentRM Subsystem has been started. Subsystem PID is 1101904.
0513-059 The IBM.AuditRM Subsystem has been started. Subsystem PID is 15061228.
0513-059 The IBM.ServiceRM Subsystem has been started. Subsystem PID is 10711274.
0513-059 The IBM.ERRM Subsystem has been started. Subsystem PID is 1028290.
0513-059 The IBM.HostRM Subsystem has been started. Subsystem PID is 7888986.
0513-059 The IBM.DRM Subsystem has been started. Subsystem PID is 7745610.
0513-059 The IBM.LPRM Subsystem has been started. Subsystem PID is 12681286.
gzaix@root:/home/root # lssrc -g rsct_rm   
Subsystem         Group            PID          Status 
 IBM.CSMAgentRM   rsct_rm          1101904      active
 IBM.AuditRM      rsct_rm          15061228     active
 IBM.ServiceRM    rsct_rm          10711274     active
 IBM.ERRM         rsct_rm          1028290      active
 IBM.HostRM       rsct_rm          7888986      active
 IBM.DRM          rsct_rm          7745610      active
 IBM.LPRM         rsct_rm          12681286     active
gzaix@root:/home/root # lssrc -a | grep rsct
 ctcas            rsct             11706538     active
 ctrmc            rsct             13627430     active
 IBM.CSMAgentRM   rsct_rm          1101904      active
 IBM.AuditRM      rsct_rm          15061228     active
 IBM.ServiceRM    rsct_rm          10711274     active
 IBM.ERRM         rsct_rm          1028290      active
 IBM.HostRM       rsct_rm          7888986      active
 IBM.DRM          rsct_rm          7745610      active	[b]<- for your information, this is actually the key component for DLPAR operations[/b]
 IBM.LPRM         rsct_rm          12681286     active

2. If you are on this point, it means that the point 1 was not enough. No problem; execute the following and check if all is running. Sometimes you will have to wait for a minute or so before verifying if all is running.

gzaix@root:/home/root # /usr/sbin/rsct/bin/rmcctrl -z
gzaix@root:/home/root # /usr/sbin/rsct/bin/rmcctrl -A
gzaix@root:/home/root # /usr/sbin/rsct/bin/rmcctrl -p

gzaix@root:/home/root # lssrc -a | grep rsct
 ctcas            rsct             11706538     active
 ctrmc            rsct             13627430     active
 IBM.CSMAgentRM   rsct_rm          1101904      active
 IBM.AuditRM      rsct_rm          15061228     active
 IBM.ServiceRM    rsct_rm          10711274     active
 IBM.ERRM         rsct_rm          1028290      active
 IBM.HostRM       rsct_rm          7888986      active
 IBM.DRM          rsct_rm          7745610      active
 IBM.LPRM         rsct_rm          12681286     active

Now try again the DLPAR operations. Sometimes you have to wait few minutes. If it's still not working, go to point 3.

3. Use recfgct to delete the RMC database, do a discovery and recreate the configuration. In many cases, it is safe to be used except on the cases where the LPAR is a CSM Management Server or RMC Virtual Shared Disks (VSDs). You can verify if you have such configuration with the following commands:

For CSM:

lslpp -L | grep csm

For VSD:

lslpp -L | grep vsd

If nothing it's installed, you are good to go. More information about this specificity you cand find here: https://www-304.ibm.com/support/docview.wss?uid=isg3T1010615

Anyway, assuming that your lpar is not among those 2 situations above, you can execute the following:

gzaix@root:/home/root # /usr/sbin/rsct/install/bin/recfgct
0513-071 The ctcas Subsystem has been added.
0513-071 The ctrmc Subsystem has been added.
0513-059 The ctrmc Subsystem has been started. Subsystem PID is 13713506.

sincyc1@root:/home/root # lssrc -a | grep rsct
 ctrmc            rsct             13713506     active
 IBM.CSMAgentRM   rsct_rm          12763234     active
 IBM.ServiceRM    rsct_rm          11706426     active
 IBM.AuditRM      rsct_rm          12910790     active
 IBM.ERRM         rsct_rm          12320870     active
 ctcas            rsct                          inoperative

... sometimes you have to wait for all to be up ...

sincyc1@root:/home/root # lssrc -g rsct_rm
Subsystem         Group            PID          Status 
 IBM.CSMAgentRM   rsct_rm          12763234     active
 IBM.ServiceRM    rsct_rm          11706426     active
 IBM.AuditRM      rsct_rm          12910790     active
 IBM.ERRM         rsct_rm          12320870     active
 IBM.LPRM         rsct_rm          15061022     active
 IBM.HostRM       rsct_rm          13308084     active
 IBM.DRM          rsct_rm          10186814     active

If you still have problems, then you may have to restart the HMC or check the connections between the HMC and the Squadron. You can check some HMC commands to help you out with that.