Forum Discussion

sow_12731's avatar
sow_12731
Icon for Nimbostratus rankNimbostratus
Aug 11, 2008

SNMP Pool Member data

Hello,

 

 

I am trying to use Cacti to graph connection information about my server pool members. This requires me to know how to get this information using SNMP for each individual server. I have found a way to use snmpwalk and an OID to get this information for all pool servers, but I have not found an OID that will work for just one pool server.

 

 

Has anyone else tried to do this? I'm a little bit at a loss to figure out what I need.

 

 

Thanks

 

SOW
management
monitoring
  • JRahm's avatar
    JRahm
    Icon for Admin rankAdmin
    Aug 11, 2008
    I haven't been successful with the pool member due to the way the oid is indexed. I plan to write an external script (called by Cacti) to grab the stats via IControl. I haven't yet had the time (or the skill) to accomplish this. If I ever get there, I'll be sure to post. This would be a tremendous addition to the template.
  • sow_12731's avatar
    sow_12731
    Icon for Nimbostratus rankNimbostratus
    Aug 11, 2008
    Thanks, citizen,

     

     

    Can you tell me a little bit more about the way the OID is indexed and why it's stopping me?

     

     

    Also,

     

    Maybe this is a better topic for a cacti forum, but, can you talk a little about how you might architect a script and/or cacti data gathering techniques to make this happen the way you describe? I'm (obviously) not well-versed in cacti or SNMP, but I can write the stuffing out of a script.

     

     

    Do you have the same problem I do with being able to get data for all pool members, but not for one?

     

     

    Thanks.

     

    SOW
  • JRahm's avatar
    JRahm
    Icon for Admin rankAdmin
    Aug 14, 2008
    Sorry. OK, so if you walk the ltmpoolmemberstat mib for example, you get (sample output):

     

     

    F5-BIGIP-LOCAL-MIB::ltmPoolMemberStatServerBytesIn."int-pool".ipv4."10.10.1.10".443

     

    F5-BIGIP-LOCAL-MIB::ltmPoolMemberStatServerBytesIn."int-pool".ipv4."10.18.1.11".443

     

     

    Notice that the pool definition, which is what cacti would use as the index for each pool member, is in the middle of the string, not at the end, as in the virtual server definition. The numerical representation is below, with the index highlighted.

     

     

    .1.3.6.1.4.1.3375.2.2.5.4.3.1.6.11.105.110.116.45.112.111.111.108.1.4.10.1.1.10.443

     

    .1.3.6.1.4.1.3375.2.2.5.4.3.1.6.11.105.110.116.45.112.111.111.108.1.4.10.1.1.11.443

     

     

    My experimentation with the regex in the xml file always led to a double dot in the oid string used to query the LTM, which obiously failed.

     

     

    I'm not sure how to approach from the script side. I think it would be ideal to figure out a way to have Cacti "discover" the pools and pool members from an iControl script, then use iControl to populate the rrd files as you define what to graph in the device page. I think a thread on Cacti forum would be the best bet for this help, and we can reach out to Joe here at DevCentral on the iControl specific pieces.