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Eddie_Adams_179's avatar
Eddie_Adams_179
Icon for Nimbostratus rankNimbostratus
Jan 21, 2015

Best practices for re-clustering a broken cluster?

Hopefully, this is the proper area to ask this, and if not, please let me know where it should be posted.

 

I have inherited a pair of 3900 LTM's that had apparently, at one time, been clustered. Both units are at different software versions: 11.1.0 HF2, and 11.2.1 HF7. One of the units shows that it is standalone, and the other shows as disconnected beneath the Online (Active) indicator at the top-left side of the management gui. Both have differing virtual servers, certificates, profiles, etc... I have been tasked with re-joining them together as a cluster.

 

I am still fairly green with the more advanced topics on F5's, and would like to know if anyone can suggest a course of action for rejoining them together. I am very familiar with the underlying concepts and technology, but need to know do I need to mirror the profiles, certs et al, or can I consolidate the profiles, certs, networks and such on one, and then re-cluster them, after getting both a more current, matching software rev? Any help would be greatly appreciated.

 

Thanks!

 

application delivery
availability
deployment
design
LTM

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  • Eric_St__John's avatar
    Eric_St__John
    Icon for Employee rankEmployee
    Jan 21, 2015

    The best course of action would be to take one of the devices offline, re-create all of its objects on the device which is still online, clear the configuration on the offline device, create the basic configuration necessary to configure HA(VLANs and Self IPs), then configure HA between the devices.

     

    Recreation of the objects does not have to be as tedious as it sounds. While I would not advocate making configuration changes directly to the /config/bigip.conf file, you can copy portions of that file such as the monitors, profiles, pools, and virtual servers into a new file, move it to the online BIG-IP, then use 'tmsh load /sys config file FILENAME merge' to merge the configuration from that file into the online BIG-IP.

     

  • Arnaud_Lemaire's avatar
    Arnaud_Lemaire
    Icon for Employee rankEmployee
    Jan 21, 2015

    That's not an easy one, it's like merging two standalone bigips. Synchronization doesn't support merging configuration.

     

    i would take the road of the scf and try to verify the import :

     

    on first machine 1) save sys config file -> save configuration to files 2) copy file and archive to second machine ons second machine 3) load sys config file <> merge verify 5) if ok remove verify to merge, then save sys conf, if needed remove all on ltm/sys related object from the scf 6) re create the cluster and synch from second

     

    scf overview : https://support.f5.com/kb/en-us/solutions/public/13000/400/sol13408.html

     

  • Eddie_Adams_179's avatar
    Eddie_Adams_179
    Icon for Nimbostratus rankNimbostratus
    Jan 21, 2015

    Thank you kindly. Now, I have a reasonable plan that I can break down into smaller, bite-size chunks. I'm off to find some white-papers on configuring HA and the CLI. As of yet, I've been able to accomplish everything through the GUI. I'm a Cisco / Linux guy, so the CLI isn't overly daunting, thankfully. Thanks again for the help!