Low IRAT success rate due to Relocation Failure in Target CN/RNC or Target System

[telcofans]

Hi all,

I am facing a problem low IRAT SR, found many fail due to Relocation Failure in Target CN/RNC or Target System.
The counter is IRATHO.FailRelocPrepOutCS.TgtFail and i have no idea where the problem come from. I also found fail with SEMATIC ERROR reason.
Is it parameter in MSC or BSC? just for information. MSC and BSC using other vendor.

Thank You

[Budaxbaix]

Hi,

I found similar case, may be the root cause is same with yours
RELOC FAIL IN TARGET CN RNC OR TARGET SYS => AMR activation on 2G MSC
SEMATIC ERROR => No 2G Cells Information Configured in 3G MSC, there is possibility LAC/CI changing in 2G side which not update/register yet in 3G MSC.

Here is the document for more detail.
Low CS Inter-RAT -semantic error - fail in target CN RNC or target system.rar

Thanks

[rjcell]

I found IRAT preparation fail duo to No Resource Available, is it congestion/blocking in 2G due to high traffic?

[boring]

I found IRAT preparation fail duo to No Resource Available, is it congestion/blocking in 2G due to high traffic?

yeap this is the case, when targte BSC cannot alocate a TCH at target cell

[gprastomo]

Hi Igot the same issue, but this problem appear suddenly from 95% to 20%, i guess there was MSS Activity.
I checked the LAC creation and DPC OPC of the BSC, mostly correct but i found some LAC have issue, but lets seethe result after correcting this issue.

[gprastomo]

Hi I Just got finding that definition of 2G Cell ID in 3G was wrong so it gave wrong destination, and in CN it generate unknown Cell.

so you need to check the consistency inlcuding the cell id