Nokia LTE SRB1 SRB2 DRB (M8007C9 / M8007C12 / M8007C2 res)

[anita_2k]

Equipment: Nokia
Tech: LTE

hello, anybody experience the sudden increase on these 3 counters in LTE.
difficult to track since we have so many activities in parallel.

LTE rollout / consistency alignment and everything i am managing so i know nothing was modified/no parallel activity etc...
I am also blind about the MME (cisco was the MME)
I am blind in 2G (in house by the operator)
3G rollout - no increase in traffic on all nearby 3G sites / no physical adjustments as well along vicinity

i plan to do some old school reset first and see what happened...

might be somebody here have similar cases? please share.

stupid network / everything are mix.

note: increment on counters are noticed M8007C9 / M8007C12 / M8007C2

thanks
Anne

LTE_Signalling_Failures_Increase2.jpg

[anita_2k]

i believe this is related to Cisco MME since we also have increment on failure counters which are initiated by EPC/EPS.
all sites identified with similar increase in failure at signalling bearer are situated near TAC border (suspected to be the issue). Blinded since we have different MME vendor.
might be, the sites are having TAU issue or something but the vendor was hiding it and which we still do not know as of the moment.

imsi trace / some sort of tracing was our next pending action.

anyway, if somebody has other opinion or suggestion / experience, please share.

note: reset has no effect

thanks
Anne

[mhelboy]

Hi Anita_2K,


We also have that kind of problem with RL30 Version of LTE before last year. It was a software Issue as per analysis of the Korean LTE expert.
Problems due to SRB1 Failures/ (0% RRC) were not evident anymore in newly on-aired sites with RL40 or RL50 versions of LTE.

Note: Nokia already dropped the support for RL30 Version.

ID	Counter name in view	NE counter name	Problem
M8007C9	SRB1_SETUP_FAIL	SRB1 setup failures	Gradually increasing everyday until SRB1 Setup SR becomes 0%
M8013C6	SIGN_EST_F_RRCCOMPL_MISSING	Signaling Connection Establishment failures due to RRC Setup completions missing	Gradually increasing everyday until Total E-UTRAN RRC Connection Setup Success Ratio(LTE_5281C) becomes 0%

PS: Pwede ba kitang maging Idol?

i believe this is related to Cisco MME since we also have increment on failure counters which are initiated by EPC/EPS.
all sites identified with similar increase in failure at signalling bearer are situated near TAC border (suspected to be the issue). Blinded since we have different MME vendor.
might be, the sites are having TAU issue or something but the vendor was hiding it and which we still do not know as of the moment.

imsi trace / some sort of tracing was our next pending action.

anyway, if somebody has other opinion or suggestion / experience, please share.

note: reset has no effect

thanks
Anne

[anita_2k]

i will forward you the email of your korean expert widrawing from our email exchange. ehehe... sumuko na yung expert niyo sakin. ehehe

mak-yu mhelboy.

thanks
Anne

Hi Anita_2K,


We also have that kind of problem with RL30 Version of LTE before last year. It was a software Issue as per analysis of the Korean LTE expert.
Problems due to SRB1 Failures/ (0% RRC) were not evident anymore in newly on-aired sites with RL40 or RL50 versions of LTE.

Note: Nokia already dropped the support for RL30 Version.

ID	Counter name in view	NE counter name	Problem
M8007C9	SRB1_SETUP_FAIL	SRB1 setup failures	Gradually increasing everyday until SRB1 Setup SR becomes 0%
M8013C6	SIGN_EST_F_RRCCOMPL_MISSING	Signaling Connection Establishment failures due to RRC Setup completions missing	Gradually increasing everyday until Total E-UTRAN RRC Connection Setup Success Ratio(LTE_5281C) becomes 0%

PS: Pwede ba kitang maging Idol?

[anita_2k]

another thing Mhelboy, we do not have problem anymore on total RRC or cssr LTE_5281C since alignment of PUCCH dimensioning for LN3.xx sites.

what left now are pure signalling radio bearer failures.

i will try tomorrow morning to spit the failures between LN3.xx and LN4.x/LN5.x to see the breakdown of the failures.

Thanks
Anne

Hi Anita_2K,


We also have that kind of problem with RL30 Version of LTE before last year. It was a software Issue as per analysis of the Korean LTE expert.
Problems due to SRB1 Failures/ (0% RRC) were not evident anymore in newly on-aired sites with RL40 or RL50 versions of LTE.

Note: Nokia already dropped the support for RL30 Version.

ID	Counter name in view	NE counter name	Problem
M8007C9	SRB1_SETUP_FAIL	SRB1 setup failures	Gradually increasing everyday until SRB1 Setup SR becomes 0%
M8013C6	SIGN_EST_F_RRCCOMPL_MISSING	Signaling Connection Establishment failures due to RRC Setup completions missing	Gradually increasing everyday until Total E-UTRAN RRC Connection Setup Success Ratio(LTE_5281C) becomes 0%

PS: Pwede ba kitang maging Idol?