"partition" priority in CSS means?

[Pointbreak]

Hi experts,

What actually means when you keep partition in priority in CSS page.

It would appreciated anyone explains it with example.

[Chris Deren]

As you probably know CUCM uses more explicit match and partition order in CSS is a tie breaker between 2 exact same matched patterns. Consider CSS with partitionA and partitionB (in that order), there is pattern 2XXX assigned to partitionA and another 2XXX (identical) to partitionB, when someone using this CSS dials anything in 2XXX range it will use the order of partitions and match the pattern in partitionA only.  

[Jaime Valencia]

They don't need to be the exact same pattern, they just need to match the same number of possibilities.

Some time ago someone asked if there would be any preference between something like 1[2345]0 and 1[2-5]0 and CUCM considered them both equally good matches.

[Chris Deren]

Sure, I guess I did not think about that as that would make very little sense to define patterns that way, but in system with many cooks that's certainly possible. In either way, order of PTs in CSS comes into play to determine which pattern should be used when 2 matches are tied for the same explicit match.

[fedor.solovev]

Hello, Chris.
I am dealing with almost the same question: but I guess that my schema eventually shouldn't work.

• we have CUCM1 with IP Phones with numbers from the range [2-5]XXX and a new CUCM2 clusters.
• we are going to re-register some portion of phones with numbers 3xxx from the CUCM1 to CUCM2.
• 3xxx phones will not be deleted from the CUCM1 during some time.
• I am trying to reroute calls at 3XXX from CUCM1 to the CUCM2 if IP phones at CUCM1 are unregistered.
• There is a working SIP trunk between two CUCMs configured.
• The test called number is 3333. This phone is unregistered at CUCM1 and registered with CUCM2.

So, at CUCM1 I have CSS_REROUTING with PT_DEVICES and PT_3XXX_REROUTING in the exact order.

RP 3xxx in the PT_3XXX_REROUTING is configured pointing to RL -> RG -> SIP-TRUNK-CUCM2

CSS_REROUING is assigned to a Calling Device.

I tried to change the order of the PTs in the CSS_REROUTING, but the rerouting is working only if RP points explicitly to 3333 (test) number and PT_3XXX_REROUTING is higher then PT_DEVICES.