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chamindak_11539's avatar
chamindak_11539
Icon for Nimbostratus rankNimbostratus
Jun 19, 2014

How to rename a vcmp guest?

Hello, I am in a situation where I need to change the guestname of a vCMP guest. Changing the hostname of the guest can be done easily. However changing the guestname appears tricky. I can see the guest name is defined on bigip.conf on the vCMP host. If I change the guest name on bigip.conf, then do a "bigstart restart vcmpd" would this update the guest name?

 

Also the question is would restarting vcmpd cause an outage for the other guests that are running on the host?

 

Many thanks for any suggestions, CK

 

deployment
management
virtualization
  • Steve_M__153836's avatar
    Steve_M__153836
    Icon for Nimbostratus rankNimbostratus
    Jun 19, 2014

    The only way I know of is to do what you are suggesting...edit the bigip.conf file. After you do that you'd have to reload the config 

    tmsh load sys config
    and then save the config 
    tmsh save sys config
    . According to F5 "This daemon, named vcmpd, performs most of the work to create and manage guests, as well as to configure the virtual network." If it weren't for that part about the network you might be safe restarting the daemon, but I think I would play it safe and make sure all your guests are standby on that chassis, then shut down the guests, make the changes to the bigip.conf file, load/save your config, restart the service, and power the guests back on.

  • chamindak_11539's avatar
    chamindak_11539
    Icon for Nimbostratus rankNimbostratus
    Oct 20, 2014

    We went with re-creating the VCMP and cutting over onto the new instance. The client wanted to minimize any downtime..

     

  • anubis24_5555's avatar
    anubis24_5555
    Icon for Nimbostratus rankNimbostratus
    Feb 23, 2015

    Renaming the vcmp guests by editing the bigip.conf file, reloading and saving the config and then restarting vcmpd.conf worked for me with no issues. There was however downtime although minimal. IMHO it was much faster than rebuilding the instances.

     

  • mkratochvil's avatar
    mkratochvil
    Icon for Cirrus rankCirrus
    Apr 13, 2018

    I will rephrase the question, to understand it better: After I create a vCMP guest initially, its config is in hosts's bigip.conf and also in guest's bigip_base.conf. Which one of these has priority? What will happen if I simply change the device name on the guest? Will I have conflicting configs between the guest and the host? If I reboot the host, will revert the gust name back to the old one?

     

    Thanks for any advice.

     

  • mkratochvil's avatar
    mkratochvil
    Icon for Cirrus rankCirrus
    Apr 19, 2018

    And what about the vdisk? It gets created based on the guest name? Did you change the vdisk name as well to match the new guest name?

     

    Thanks

     

  • MUHAMMAD_ALI_JI's avatar
    MUHAMMAD_ALI_JI
    Icon for Nimbostratus rankNimbostratus
    Aug 14, 2018

    I have used another vendor Product. Guest name change there can be done from the Management VM and it will automatically update the guest as welll . Nothing to worry about the disk files associated with it either. With F5, I have noticed that there is a "Name" object and Hostname Object for a guest on the VCMP Host. Name Object looks more like a descriptive name for the guest ( but I set the Name & Hostname to be the same). And the disk file seems to follow the Name & not the Hostname Object. So from within VCMP Guest & Host I was able to modify the Hostname. But there is no option to modify the Name & the Virtual Disk file associated with it. Disk img file would still reflect the old "Name" though you have changed the guest's Hostname. That's a discrepancy to live with. Else do a cleaner deployment of deleting and recreating a new VCMP Guest with the desired names during a maintenance window.

     

    Would like to see any other thoughts on this ?

     

    Thanks

     

  • Phil_Keyser's avatar
    Phil_Keyser
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    Jan 09, 2019

    I was able to get this to work. One main thing to do while the guest is still up is login to the cli and run 

    f5mku -K
    to get the current Master Key. It seemed to change so it couldn't read the config after I performed the steps below. I made sure all of my guests were disabled and offline(Your Guests will be restarted when you restart vcmpd below if they are running). I then edited 
    bigip.conf
    and changed the 
    guest name, hostname, and the virtual disk name
    . I then went into 
    /shared/vmdisks
    to change the virtual disk name using 
    mv old_name.img new_name.img
    . Then I did 
    tmsh load sys config
    tmsh save sys config
    bigstart restart vcmpd
    . I noticed in the Viprion GUI the old virtual disk was still listed with the old name but a size of 0 so I deleted that. The new renamed image will also be there. Don't delete the new one. Once I deployed the renamed guest it will come up into an INOPERATIVE state and the gui will not load. I connected via SSH to the CLI and restored the Master Key using 
    f5mku -r key
    using the key you got above. Then a final 
    tmsh load sys config
    on the LTM CLI and I was back in business with everything using the new name. You will probably have to do some other steps like updating the LTM Device SSL Certificate to match the new hostname. You also need to go to Device Management > Devices > device_name > Click 
    Change Device Name