DRS recovery involving PLM server

[Clifford McGlamry]

I have customers asking legitimate questions regarding business continuity and DRS recoveries.  One that has come up repeatedly is regarding the Licensing Manager servers.

The documentation I have seen is very obscure about what exactly the licenses are tied to, saying only that if "the hardware is replaced, rehosting may be required".

So, I'm going to ask this in a very upfront manner, and hope to get a clear answer.  I think the customers are entitled to understand this, and Cisco really needs to be clear about it.

What EXACTLY are the PLM licenses tied to?  Is it the UUID of the server, the MAC address?  Some combination of things (like in pre version 9....and if so, WHAT?)?

Customers are wanting cookbook procedures for business continuity and we are attempting to determine what can be done to have to avoid license rehosting in the event a data center is taken out by a flood, airplane crash, etc.

TIA for any assistance.

Cliff

[Manish Gogna]

Hi Cliff,

Licenses in 9.X and higher versions are tied to the ELM/PLM server's UUID instead of the publisher's license MAC address.

Also,

License Rehost

Licenses are fulfilled to a specific Cisco Prime License Manger. If you require licenses to be moved to a new Cisco Prime License Manager, they will be need to be rehosted.

A rehost may be required if:

• A hardware failure occurred and new hardware is required for Cisco Prime License Manager
• Multiple Cisco Prime License Managers are desired and a subset of fulfillment licenses need to be moved to a new Cisco Prime License Manager

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/plm/10_0_1/userguide/CPLM_BK_U7066CD8_00_user-guide-rel-10-0-1/CPLM_BK_U7066CD8_00_user-guide-rel-10-0-1_chapter_01000.html#CUCM_TK_L403A667_00

Manish

[Clifford McGlamry]

Based on testing I'm doing in my lab, this is not entirely accurate.

If I use VMWare and clone the license server (with a manually set MAC address), the server id doesn't change.

I can change the ip address of the server, and the server id doesn't change.  

I can move it to another host, with a completely different set of physical (and different type) hardware, and it doesn't change.

BUT, if I change the MAC address, the server ID DOES change.  

If I change the MAC address back to the originally set value, the Server ID changes again, but NOT back to the original value!

Not clear why the UUID would change if the MAC changes, but I suspect that the MAC and possibly the UUID along with the date/time may all factor into this.  

Like I said, the docs are not clear on this.  While I understand Cisco attempting to protect the integrity of the licensing process, I do think more info is needed in the field. 

[Manish Gogna]

Hi Clifford,

Thanks for sharing the details of your testing. I stumbled upon the following bug which confirms what you are experiencing as expected behavior

https://tools.cisco.com/bugsearch/bug/CSCul66335/?reffering_site=dumpcr

PLM should warn if license request attempted with dynamic MAC address

CSCul66335

Description

Symptom:
Prime License Manager (PLM) uses the mac address of eth0 when creating the UUID to which its license is assigned. If this UUID changes then the active license will be invalidated.

Cisco has documented recommendations for customers to assign a static mac address to virtualized Enterprise License Manager and Prime License Manager.

If a dynamic mac address is assigned to a virtualized PLM then any potential changes to the host, vNic or other configurations can result in the dynamic mac address changing.

Conditions:
Cisco Prime License Manager running in a VMware virtualization infrastructure.

Workaround:
Follow Cisco documented procedures to assign a static mac address to the vNic of the PLM server or Cisco Unified Communications Manager (UCM) if PLM runs co-resident with UCM.

Further Problem Description:
This is an enhancement to get PLM to warn the user if it detects a dynamic mac address is being used so that there is no exposure to a potential license rehost in the future if the mac address changes.

Manish