How to troubleshoot failures after admission

[ionicwaves]

In E******* WCDMA networks, there are many failures after admission affecting CS and PS accessibility KPI.
Though there are some documents which list certain things to check for this failure, are there any definite list of things to check which will help to identify the failures that cause failures after admission.

[babak1349]

In E******* WCDMA networks, there are many failures after admission affecting CS and PS accessibility KPI.
Though there are some documents which list certain things to check for this failure, are there any definite list of things to check which will help to identify the failures that cause failures after admission.
Hello
After admission means that, the resources are available and can be allocated to users (Radio and BB resources) but the RRC or RAB establishment fails after resource allocation which could be due to:
1) TN issue (capacity & config failure)
2) Nodeb failure
3) check always pmTotNoUtranRejRrcConnReq counter as well. Which includes admission rejection (so you need to compare it with RRc rejected by admission) some times it is high because of failure in NodeB maybe due to hanging resources ( restarting the nodeB may help)
3) Radio air interface failure

you can activate UE Exception or CTR to find more

BR


You can look at the Iub link performance and errors ( frame lost, iub limiting)

[ionicwaves]

Thanks for the reply babak1349. Am seeing cases where the pmTotNoUtranRejRrcConnReq is very less and only pmnofailedafteradm is very high even during off-peak hours. checked Iub KPIs, no issues found (frames lost, availability, congestion). Tried NodeB restart also which did not help.
im suggesting to change the DUW30, but the customer is not willing, asking to fine tune any parameters possible. Any suggestions here?

[electron]

Thanks for the reply babak1349. Am seeing cases where the pmTotNoUtranRejRrcConnReq is very less and only pmnofailedafteradm is very high even during off-peak hours. checked Iub KPIs, no issues found (frames lost, availability, congestion). Tried NodeB restart also which did not help.
i'm suggesting to change the DUW30, but the customer is not willing, asking to fine tune any parameters possible. Any suggestions here?

Hi,

Some missing configuration also causes after admission failure. for example u set 64 EUL users but numehichergchcodes set to 2 ! It is pretty much difficult to make sure in Iub /IP that signalling plane is really fine if you have chance at first check any performed activity on transmission side upon appearing the issue in previous days.


Cheers