RRC connection setup failures because of limitation of UE number specifications

Hi All.

Any sugestions about L.RRC.SetupFail.ResFail.UserSpec failures in 4G Huawei?

Number of RRC connection setup failures because of limitation of UE number specifications.

Admin note: this post was updated with image below.

Maybe you reached max number.

Not sure is it 150 or 300?

I mean max RRC users per cell is 150 or 300?

You can get rid of this issue by sharing some traffic with neighbour cells.

Change some CIO with neighbour cells and get rid of 5-10% of traffic.

Use IMLB or IFLB for shifting traffic.


Change this parameter to LARGECAPACITY… It will increase from 1200 to 1900 users.

First check the hardware specification.

For lampsites for example this parameter cause outage of cell.

You have to increase the RRC user license.

I think that the problem isn’t licence, maybe it is Hardware.

LBBPd2 suports only 1200 users.

Try to switch users in idle mode.

Check PRB and Volume.

This does not necessarily show the max utilisation on site.

The number of UL synchronized UEs supported by an LBBP can reach 3600 by specifying the MaxSyncUserNumPerBbi parameter. The increase of UEs, however, may cause user experience and system performance to deteriorate. Therefore, it is not recommended that this parameter be used to increase the number of supported UEs to over 1200.

What is the trend of user max in BH?

What is the peak value?

Max user is around 1400 in BH.

1 line per sector.

Mmm I see. This is weird.

But at the same time you can see that the two peaks of failures correlate with the 2 peaks of user number.

This can be due to some hardware alarm or RRU issue in that time.

Seems Max UL Synchronized UEs Above BBP board specification.

It is recommended that the BBP board be replaced with a board with a higher processing capability.

But in this case the eNB will accept the user license number configured to exceed the board capability?

Seems the configuration of Max UL Sync UEs is less than the maximum RRC users which trying to camp on the node.

We can increase the Max UL Sync UEs if the BBP board can support, need to check the specification of existing board.

And if not supported, need to change the BBP board.