What are the reason for L.NsaDc.SCG.Change.Failure.TNL, which increased abruplty on top sites from last 3 days.
gNB - SGW transmission issues, packet loss.
I had the same problem here: Check if X2 alarm exist between the site where this alarm appears.
This alarm means that you have a problem with PSCell Change.
Yes, I have checked one site. There is x2 interface fault alarm when issue occur and till now not cleared.
So, you need to solve that first.
I suggest to solve the X2 alarm first. Try to do a PING between CP from Host to Peer.
Also, check it:
Using the command you will check the “SCTP Link Failure” and can to check who is the Peer problem in “X2 Interface CP Bearer ID”.
LST SCTPLNK:SCTPNO=X2 Interface CP Bearer ID;
Using this you will have the both IPs (Local and Peer), so, try to do a PING.
Look my result: Problem between both.
Check also if your Counter (N.NsaDc.InterSgNB.PSCell.Change.Fail.Trans) increase.
If you really have a X2 problem, you´ll probably also have a trouble on this counter:
N.NsaDc.InterSgNB.PSCell.Chance.Fail.Trans: Number of inter-SgNB PSCell change failures caused by transmission faults in LTE-NR NSA DC scenarios.
I Suggest also, check and TURN ON both switches:
LTE_NR_X2_SON_SETUP_SW - GlobalProcSwitch.InterfaceSetupPolicySw (eNodeB side)
X2SON_SETUP_SWITCH - gNBX2SonConfig.X2SonConfigSwitch (gNodeB side)