Solve "rlc-MaxNumRetx" and "synchReconfigFailureSCG" failures

What is your value of n310, T310, n311, t311 in 5G?

Is it in 4G end or 5G end?

It’s for 5G.

You know that samsung terminals disconnect 5G when over heated, right?

1 Like

I don´t know…maybe.

This is confirmed for Samsung S21.

Over 43 degrees it cuts 5G:

Hum… Thanks for the info.

Nowadays in my NET we only have 3 terminals models working in NSA Network (b3_b7_N1):

  • Huawei P40
  • Motorola Edge 5G
  • and recently (this week), Samsung S21.

Overheating in UE can be one reason for failure, but also coverage will trigger same messages.
As I said you can’t expect 100% of those failures in your network are due to terminal issues.
Some are also caused by RF.
LACK of 5G coverage, missing 4G-5G relations
AT the end of 5G coverage do you have an A2 event to release the SCG?

I didn´t check it. Why?

If it is set too low, then chances of SCG failures are high.

I mean when your UE walks out of 5G coverage what message do you expect to see in 5G and what counters you expect to be incremented?
Just remember that 5G serving cell is very different from 4G serving cell.
Even when are the same footprint of antenna is very different in 4G and 5G.

A2 it set as -121 dBm.
Is this -121dBm value good?

It depends upon what is your SINR /RSRQ at such low RSRP.
But in our case also it is -121 dBm.

It depends on your NR coverage.
If you have good overlapping between 5G cells you will never reach -121 dBm so A2 won’t be triggered.
But I am asking again: “I mean when your UE walks out of 5G coverage what message do you expect to see in 5G and what counters you expect to be incremented?”

Huawei gave explanation to all MNOs as DRB abnormal in Huawei network is very high like 10% so HW is recommending to use only SgNb abnormal release for actual Drop rate KPI.
We had many discussions and no outcomes.
For Apple, it is using T310 expiry with special signature and there is parameter in Huawei to exclude those SCG failure due to over heating or power protection.
But still DRB abnormal release is having major portion from UE vendor own mechanism to release SCG with fake cause.

1 Like

Is this the parameter related to handle over heating?


If yes, I don´t have in my actual release (16.0).
Is it available only in 16.1.

It is reserved parameter.


Question: it work only for Apple?

Checked, it’s OFF in my NW.

It seems like that.
As Apple team clarified that it is using special signature with SCG Failure T310 Expiry PCI 000.
If other vendors are also having unique signature for over heating SCG failure, Huawei can exclude in upcoming release.
As only Apple confirmed this mechanism, it meant exclusively for iPhones.

If you have many iPhone users please make it ON so it will exclude those abnormal release and DRB abnormal release will improve.

Apple may also disable SCG autonomously (via SCG failure) under low traffic scenarios, not only overheating.

1 Like