SR5251060 Root Cause Analysis for RRC Setup Success Rate degradation Issue
011
Date
2010-07-0219
HUAWEI TECHNOLOGIES CO., LTD.
Issue 01 (2015-10-19)
Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd
1
Copyright © Huawei Technologies Co., Ltd. 2010. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.
Trademarks and Permissions And other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders.
Notice
The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either expressed or implied. The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute the warranty of any kind, express or implied.
Huawei Technologies Co., Ltd. Address:
Huawei Industrial Base Bantian, Longgang Shenzhen 518129 People's Republic of China
Web site:
http://www.huawei.com
Email:
[email protected]
Issue 01 (2015-10-19)
Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd
3
SR5251060 Root Cause Analysis for RRC Setup Success Rate degradation
Contents
About This Document Trouble Ticket Information Trouble Ticket Number
5251060
Prepared by
Huanghui 00206795
Approved by Approval Date
2015-10-19
Revision History Issue
Date
Author
Change Description
01
2015-10-19
Huanghui 00206795
First Version
SR5251060 Root Cause Analysis for RRC Setup Success Rate degradation
Contents
1
Contents
About This Document......................................................................iii 1 Basic Information.......................................................................1-1 2 Problem Description...................................................................2-1 3 Problem Analysis.......................................................................3-1 3.1 The Degradation of RRC Setup SR is mainly caused by L.RRC.SetupFail.NoReply...................................3-1 3.2 TOP UE Cause the RRC Setup Success Rate degradation in the Site LTE_Dobsonville_GSMT01_SGS....3-2 3.2.1 Analysis at 2015/10/14 05:00................................................................................................................3-3 3.2.2 Analysis at 2015/10/14 06:00................................................................................................................3-4 3.3 TOP UE Cause the RRC Setup Success Rate degradation in the Site LTE_Nupen_Rd_GSMT01_SGS......3-5 3.3.1 Analysis at 2015/10/13 01:00................................................................................................................3-5 3.3.2 Analysis at 2015/10/13 02:00................................................................................................................3-6
4 Root Cause................................................................................4-1 5 Corrective Action.......................................................................5-1 5.1 Workaround....................................................................................................................................................5-1 5.2 Solution...........................................................................................................................................................5-1
6 Preventive Action....................................................................... 6-1
SR5251060 Root Cause Analysis for RRC Setup Success Rate degradation
2
6 Preventive Action
Basic Information
Product Name
Version
BTS3900
V100R009C00SPC230
Issue 01 (2015-10-19)
Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd
1
3
Problem Description
Customer complained that two eNodeBs’ RRC Setup Success Rate degraded, as shown in Fig 2-1 and Fig 22.Huawei need to explain the degradation.
Figure 2-1 RRC Setup SR of LTE_Dobsonville_GSMT01_SGS
Figure 2-2 RRC Setup SR of LTE_Nupen_Rd_GSMT01_SGS
4
Problem Analysis
The Degradation of RRC Setup SR is mainly caused by L.RRC.SetupFail.NoReply. 4.1
From counters, RRC Setup Fail is mainly caused by L.RRC.SetupFail.NoReply, as shown Fig 3-1 and Fig 32.
Figure 3-1 RRC Setup Fail detail reason of LTE_Dobsonville_GSMT01_SGS
Figure 3-2 RRC Setup Fail detail reason of LTE_Nupen_Rd_GSMT01_SGS
L.RRC.SetupFail.NoReply Measurement Points as below:
TOP UE Cause the RRC Setup Success Rate degradation in the Site LTE_Dobsonville_GSMT01_SGS 4.2
Analysis main board log at 05:00 and 06:00 2015-10-14 for example, L.RRC.SetupFail.NoReply occured 126 and 189 on cell3.
Figure 3-3 L.RRC.SetupFail.NoReply of site LTE_Dobsonville_GSMT01_SGS
4.2.1 Analysis at 2015/10/14 05:00 Check CHR log of this time slot, also 126 records, and except first record, others have regularity, that is every 5 times is a cycle, each message interval 11~12s.
Figure 3-4 CHR log of site LTE_Dobsonville_GSMT01_SGS
4.2.2 Analysis at 2015/10/14 06:00 Check CHR log of this time slot, also 189 records, and except UE not sent 1 time , others have regularity, that is every 5 times is a cycle, each message interval 11~12s.
Figure 3-5 CHR log of site LTE_Dobsonville_GSMT01_SGS
TOP UE Cause the RRC Setup Success Rate degradation in the Site LTE_Nupen_Rd_GSMT01_SGS 4.3
Analysis main board log at 01:00 and 02:00 2015-10-13 for example, L.RRC.SetupFail.NoReply occured 20 and 21 times on site.
Figure 3-6 L.RRC.SetupFail.NoReply of site LTE_Nupen_Rd_GSMT01_SGS
4.3.1 Analysis at 2015/10/13 01:00 Check CHR log of this time slot, also 20 records, all records have regularity, that is every 5 times is a cycle, each message interval around 22s.
Figure 3-7 CHR log of site LTE_Nupen_Rd_GSMT01_SGS
4.3.2 Analysis at 2015/10/13 02:00 Check CHR log of this time slot, also 21 records, all records have regularity, that is every 5 times is a cycle, each message interval around 22s.
Figure 3-8 CHR log of site LTE_Nupen_Rd_GSMT01_SGS
5
Root Cause
RRC Setup Fail cause by UE No Reply, which cause by TOP users in live network.
6 6.1
Workaround
NA
6.2 NA.
Solution
Corrective Action
7 NA
Preventive Action
