Is it supported to change the vDisk size of a new CUCM 12.5 2500 users ova?

[Elter]

Is it supported by Cisco TAC to change the vDisk size of a new CUCM 12.5 for 2500 users ova from the default 80GB to 110GB on a new (green field) installation?

It is not to resize an already installed machine, it is a new deployment, increasing the default ova disk size.

The idea is to have more space and be prepared for future possible increase in size requirements or to avoid to run the ciscocm.free_common_space scripts or manually remove files to have enough space on upgradings.

Thanks

[Roger Kallberg]

If it’s a new installation why not use the proper OVA from the start to get the bigger disk size? But yes it should work to resize the disk before the installation. There is no magic with OVAs, it’s just a set of rules to how to create a new VM.

[Elter]

Larger ova for 7500 for example requires more resources than needed and it is not supported to reduce the ova specs.

The intention is to install the ova for 2500 directly with 110GB as disk size because after some time in use, even running the ciscocm.free_common_space to free up space sometimes it is not enough to have sufficient free disk space to upgrade.

The main question is: Is it supported? We´ll open a SR to confirm if we´ll not have problems with TAC later.

Regards

[Roger Kallberg]

Okay then I know what you mean. There are no OVA that has 110GB size disks for a 2500 deployment from what I can tell. I checked in the latest I found, cucm_12.5_vmv13_v1.0.ova. So no it would likely not be supported to change the size of the disk. As you say it's not until 7500 users that the disk is 110GB in size.

[Elter]

Cisco TAC informed that in this case, for the CUCM to be supported the .ova must be used as is.

[TONY SMITH]

I wish there was a straight and clear answer on this.  Cisco seem to change their minds.  I've seen upgrades which would only work if the disk size was increased over the OVA size, and Cisco produced the disk resizing COP specifically to allow this.

[Elter]

I agree. I´ve sent more info (bellow) to TAC and they are checking with BU...

Know disk space limitation:

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvt97709

Upgrade Document states this:

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/upgrade/12_5_1/cucm_b_upgrade-migration-guide-125x/cucm_b_upgrade-guide-1251su2_chapter_00.html#reference_14EF924A1F404FC178D81AC87B38AC1A

"Verify whether you need to change the virtual hardware specifications on your VM in order to upgrade to a new release of Unified Communications Manager or Instant Messaging and Presence. For example, verify the requirements for vCPU, vRAM, vNIC adaptor type, and vDisk size, as well as other specifications.

Any changes to a VM must align with the OVA configuration. VM changes that result in an unsupported OVA configuration are not allowed. For information about VM requirements, see Readme file with the OVA template that supports your release.

Note:

If Unified Communications Manager is upgraded to version 12.5 from version 11.5 or higher, using 80GB OVA it is expected to have a higher active partition up to 98%. We can correct this by a system rebuilt with HDD 110GB. Either use a default 110GB OVA template and rebuilt the node or on current OVA, prior to install, go to VM > Edit Settings, and increase the HDD size from 80GB to 110 GB. Other specs remain the same."

I´ll post the reply here.

[Elter · Accepted solution]

The TAC reply is: It is not supported.

"The only supported, documented way of increasing the size of the disk without risking partition alignment or performance problems is rebuilding the node using a larger OVA file."

They have raised two bugs, one that it is expected to have low space after the upgrade and the other one to fix documentation and avoid confusion.

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvt97709

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvu69050

Regards

[TONY SMITH]

I wonder where that leaves installations where the disk size was manually increased some time in the past, following Cisco documentation of the time and in some cases installing the COP specifically created for the purpose.  

[Hard_Boiled_Greg]

I have this same problem on an 11.5 CUCM server that I am attempting to upgrade to 12.5 SU3. I've done every trick I know and those suggested above to free up space but am still 5 GB short. Every time I run the ciscocm.preUpgradeCheck-00024.cop.sgn I get “12.5 Failed: You only have 24 GB of required 33 GB common partition space required for RU upgrade to 12.5.” I opened a TAC case for which the TAC engineer suggested I run the following commands:

file delete activelog cm/trace/*/*/*/* noconfirm

file delete activelog cm/trace/*/*/* noconfirm

file delete activelog cm/trace/*/* noconfirm

file delete activelog cm/trace/* noconfirm

I did that and still remained at 24 GB of free space. The TAC engineer did then suggest the following, "If this doesn’t help, please proceed to increase the size of the Vdisk, by doing this, you will not have to worry about being out of support and this should also fix the issue at all." I'm seeking a little more clarity, but it sure is being recommended by TAC to increase the vDisk size. In addition, this is taken directly from the file output after running the ciscocm.preUpgradeCheck-00024.cop.sgn tool.

"Before starting the upgrade, clear space via the following methods and reinstall this COP:
- Install latest version of ciscocm.free_common_space COP file from
cisco.com (this will delete trace/log files, current inactive version, and backed up COP files).
- For source 11.0+, use OS Admin GUI's Device Load Management to Remove Unused Firmware from the System.
- Delete any unneeded core files with "file delete" CLI.
- For source 10.x and higher, increase size of your vdisk via power down VM, edit VM specs, powerup."

That too suggests that it is supported practice to increase the size of the vDisk. I'm going to get some more information from the TAC engineer about what they suggest I increase the size to and if there are any caveats to be aware of before I pull the trigger on increasing the size.

[Roger Kallberg]

What is the disk layout for your system? If it’s a 2x80GB layout it is supported to increase the size of the second disk to 110GB. This is mentioned in official documents and we’ve done it on a couple of our systems that uses the older type of disk layout.

[Hard_Boiled_Greg]

This happens to be a very small system with a single 80 GB vDisk. 

I was provided with this official document from TAC:

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/upgrade/10_0_1/CUCM_BK_U4214F9D_00_upgrade-guide-cucm-100/CUCM_BK_U4214F9D_00_upgrade-guide-cucm-100_chapter_011.html#CUCM_TK_C9AFC8CC_00

That document verifies what you are saying about expanding the second disk if in a two vDisk environment: 

========================================================================== 

To increase the vDisk space, edit the disk size using vDisk. If the virtual machine has two disks, expand the second one.

The new space is automatically added to the common partition when you restart the virtual machine.

Note
You need to change the disk size changes only if you need additional space to complete the upgrade. The disk space requirements are specified in the Readme file for the OVA template.

Expanding the disk size to add space to the common partition will not increase the user capacity of your system. If you need to extend the user capacity of your system, you must migrate from a single-disk to a multi-disk virtual machine.

If you need to shrink the vDisk or change the vDisk quantity, you must re-install the vDisk or install a new vDisk.

==================================================================================

[TONY SMITH]

I'm maybe straying into historical rather than current systems but I think I first came across this on a 7.1.5 to 10.0.x upgrade.  Free space in common partition showed as sufficient and even said so in the logs, but the upgrade failed saying insufficient space.  The only solution was to install the "“ciscocm.vmware-disk-size-reallocation-1.0.cop.sgn" then manually change disk size in VMware settings.  I only wish I could remember whether this was under direction from TAC of from Cisco documentation or release notes.

Came across the same issue on a 9.1 to 11.5 upgrade.  And again on 8.6 to 10.5, then on an 8.6 to 11.5 then finally on another two 9.1 to 11.5.    The common factor was the 80GB disk, although some were the 1000 user profile and some the 2500.

So we really need some clarity from Cisco.  Why would they even have released that COP if it's not supported?  And where does this leave installations where disk size increase was required and advised in the release notes, if Cisco now say it is unsupported.

[Hard_Boiled_Greg]

Cisco isn't saying that it isn't supported. TAC outright told me to do it. Maybe it's who you talk to. 

Also, this is straight from the document "Upgrade and Migration Guide for Cisco Unified Communications Manager and the IM and Presence Service, Release 12.5(1)" which was just updated in July 2020.

If Unified Communications Manager is upgraded to version
12.5 from version 11.5 or higher, using 80GB OVA it is expected
to have a higher active partition up to 98%. We can correct this
by a system rebuilt with HDD 90GB/110GB. Use a default
110GB OVA template and rebuilt the node or on current 80GB
OVA, prior to install, go to VM > Edit Settings, and increase
the HDD size from 80GB to 90 GB. Other specs remain the
same.

[Elter]

Hello, this was the argument used with the Cisco TAC Engineer and after he insisted that it is not supported we requested to escalate to the BU and unfortunaltely they raised a BUG to remove this sentece from the mentioned guide:

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvu69050

Regards