[cisco-voip] increasing VM virtual memory?

Justin Steinberg jsteinberg at gmail.com
Thu Mar 10 17:02:42 EST 2016

I've increased the UCM/CUC 10.x VMs to 6 GB to prevent memory issues and
haven't had any problems.    I keep the bug below folded on some paper
tucked away in my wallet just in case.


*increase the threshold for LowAvailableVirtualMemory from 75% to 85%*

A CUCM Publisher running version 10.5(1) experiencing
LowAvailableVirtualMemory alerts.

This is most commonly seen on Publisher nodes running version 10.5(1) with
the 1k or 2.5k OVA Templates.

Increase the RTMT LowAvailableVirtualMemory threshold from 75% to 85%.


Shut down the virtual machine, increase the virtual machine memory capacity
by 2GB. This increase will be required for CUCM 11.0(1)

*Further Problem Description:*
This is not a leak or cause for concern if the VM Utilization should
stabilizes under 85%.

If Virtual Memory utilization increases above 90% there is most likely a
problem which should be investigated further

On Thu, Mar 10, 2016 at 9:53 AM, Anthony Holloway <
avholloway+cisco-voip at gmail.com> wrote:

> Nick,
> It's actually pretty common, when doing upgrades, that minimum RAM
> requirements go up, and you have to increase the allocated RAM and
> reservation.
> Example:
> CUCM 10x 2,500 OVA requires 4GB RAM
> <http://docwiki.cisco.com/wiki/Virtualization_for_Cisco_Unified_Communications_Manager_(CUCM)#Version_10.x>
> CUCM 11x 2,500 OVA requires 6GB RAM
> <http://docwiki.cisco.com/wiki/Virtualization_for_Cisco_Unified_Communications_Manager_(CUCM)#Version_11.x>
> Therefore, an upgrade on a 2,500 OVA from 10x to 11x causes a RAM increase
> And it's stated as having changed in the OVA for v11x Read Me
> <http://www.cisco.com/web/software/283088407/126036/cucm-11.0.ova.readme.txt>
> The following are changes from the OVA in the previous (CUCM 10.x) release:
>         1) vRAM size has been increased by 2GB for 11.0(1) and above releases.
> The procedure is also thinly covered in the OVA Read Me as well:
> Upgrades from previous release:
> 	1) Power off the VM.
> 	2) Modify the vRAM, CPU, reservations,and OS based on the changes listed above via the vmware-viclient. Note, do not attempt to change the number of disks or disk size.
> 	3) Modify the Network Adapter.  See “Modifying the Network Adapter” section.
>         4) Modify the VM Version if previously using VM Version 7. See "Instructions to upgrade the virtual hardware version" section.
> 	5) Save the changes
> 	6) Power back on the VM
> I say all of that, not because you indicated that you are performing an
> upgrade, but simply to illustrate that there are some cases where you MUST
> change the RAM, and therefore it makes sense that changing RAM is trivial
> and supported.  Mostly...
> Because, a negative issue I've seen come of this, is a UCCX system where
> it was originally deployed for 100 Agents, and someone increased the RAM,
> and then the system started complaining that it was a 300 Agent system with
> insufficient resources (everything except RAM).  The system was working
> fine, mind you, it was just the annoying warning banner in AppAdmin.  So,
> get the warning to go away, that person just dropped the RAM back down to
> the original value.
> On Thu, Mar 10, 2016 at 8:35 AM, Barnett, Nick <
> Nick.Barnett at countryfinancial.com> wrote:
>> Are there any negative issues that arise from increasing the RAM on a
>> CUCM 10.0 or CUC 10.5 VM?  I haven’t ever seen anyone talk about it. I
>> assume that is because there is typically an underlying issue that should
>> be resolved rather than just increasing RAM. Does anyone have any input on
>> this?
>> Thanks,
>> Nick
>> _______________________________________________
>> cisco-voip mailing list
>> cisco-voip at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-voip
> _______________________________________________
> cisco-voip mailing list
> cisco-voip at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/cisco-voip/attachments/20160310/50d82349/attachment.html>

More information about the cisco-voip mailing list