[LDM #LRI-737107]: Running 2 LDMs on single system

Justin,

> Here at NCEP we are trying to run 2 LDMs on a single node of our
> supercomputer. The LDMs are the same version, 6.7.0, but they are stored
> on separate disk partitions and run by different users.
> 
> Our system administrators have created a virtual IP on the node as
> suggested on the "Running Multiple LDM-s" page
> (http://www.unidata.ucar.edu/software/ldm/ldm-current/basics/multiple_ldms.html).
> But when I try to start the second LDM it fails saying that an LDM is
> already running.
> 
> $ ldmadmin start -v
> Aug 25 20:16:32 UTC c2n5.ncep.noaa.gov
> : start_ldm: There is another server running, start aborted
> 
> I looked at ldmadmin and see it does an ldmping to itself
> 
> $ ldmping -l- -i 0
> Aug 25 20:12:26 INFO:      State    Elapsed Port   Remote_Host
> rpc_stat
> Aug 25 20:12:26 INFO: Resolving localhost to 127.0.0.1 took 0.010277 seconds
> Aug 25 20:12:26 INFO: RESPONDING   0.012611  388   localhost
> 
> So that explains the failure. How do we get around this? I put the
> virtual IP in the $LDMHOME/etc/ldmadmin-pl.conf file where you are
> allowed to place an assignment to ip_addr. I also changed the logging to
> write to local2 but of course we never get that far.

> Both of our LDMs need to run on the c2n5 node.
> 
> Any suggestions?

Try this: in the installed ldmadmin(1) script, change

        my($cmd_line) = "ldmping -l- -i 0";

to

        my($cmd_line) = "ldmping -l- -i 0";
        $cmd_line = $cmd_line . " -h $ip_addr" if $ip_addr ne "0.0.0.0";

Let me know if that works.

> Thanks,
> 
> Justin Cooke

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: LRI-737107
Department: Support LDM
Priority: Normal
Status: Closed