S1断链告警处理指导1.故障现象描述告警管理中查看到基站上报“S1断链告警（0）”告警码，如下图所示：2.故障分析排查思路根据TD-LTE的网络接口协议，S1链路是建立在物理传输层、数据链路层、IP协议层、SCTP偶联链路之上的传输协议层，如下图所示：所以处理S1链路故障，需要从底层开始排查：1、首先排查站点是否存在传输告警，排除传输故障；2、其次基站IP地址配置是否正常；3、再次确认SCTP偶联断告警，排除SCTP偶联告警；4、最后排查是否存在S1 AP建立失败（协商失败或基站无小区），与核心网核对小区TAC值是否配置一致。
3.故障排查步骤1、查看基站告警，是否存在传输类相关告警，例如“网元断链告警”、“SCTP偶联断链”告警，若存在以上告警，需要先按照以上告警排查指导手册，先解决以上告警。
2、检查ENODEB------MME或SGW 路由IP地址是否配置正确；通过telnet命令登录到CC板，使用 BRS命令对MME及SGW地址进行PING包测试，详细登录方式如下，红色字体均需要输入：通过服务器远程登录：$ telnet 前台通过网线直连登录地址：正在尝试...连接到（）(none) login: zte（用户名）Password: zte（密码）Processing /etc/profile... Done# /ushell-> Please input password!->***（密码zte）-> Login success!!ushell tool menu: ------------------------------------------------------------------------------'ps' or 'PS' list process run on the board'pr xxx' or 'PR xxx' take over xxx process printf info'npr xxx' or 'NPR xxx' not take over xxx process printf info'db xxx' or 'DB xxx' debug xxx process printf info'ndb xxx' or 'NDB xxx' not debug xxx process printf info'pad xxx' or 'PAD xxx' debug and take over xxx process printfinfo'npad xxx' or 'NPAD xxx'not debug and take over xxx process printf info'pall' or 'PALL' display current debug and take over info'ncheck' or 'NCHECK' Do not check another ushell exist'check' or 'CHECK' Do check another ushell exist'Q' or 'q' cancel all process debug and printf info'exit' or 'EXIT' cancel ushellxxx is process id you want to debug or take over printfinfo------------------------------------------------------------------------------$$ps（查看前台进程）PID USER VSZ STAT COMMAND1 root 1304 S init2 root 0 SW [softirq-high/0]3 root 0 SW [softirq-timer/0]4 root 0 SW [softirq-net-tx/]5 root 0 SW [softirq-net-rx/]6 root 0 SW [softirq-block/0]7 root 0 SW [softirq-tasklet]8 root 0 SW [softirq-sched/0]9 root 0 SW [softirq-hrtimer]10 root 0 SW [softirq-rcu/0]11 root 0 SW [watchdog/0]12 root 0 DW [chkeventd/0]13 root 0 SW< [events/0]14 root 0 SW< [rt_events/0]15 root 0 SW< [khelper]16 root 0 SW< [kthread]17 root 0 SW< [rt_kthread]37 root 0 SW< [kblockd/0]42 root 0 SW< [khubd]83 root 0 SW [pdflush]84 root 0 SW [pdflush]85 root 0 SW< [kswapd0]86 root 0 SW< [aio/0]621 root 0 SW [mtdblockd]678 root 1253m S /680 root 9156 S /tftp683 root 1308 S telnetd685 root 1312 S inetd686 root 1312 S -/bin/./ash697 root 0 SWN [jffs2_gcd_mtd0]1201 root 457m S / 88 91 /1750 root 1316 S -sh1751 root 9216 R /ushell1753 root 1304 R sh -c ps1754 root 1308 R ps$$pad 678（登录到平台进程）[678]ushell enter print modushell enter debug mod$$brsping ""（ping核心网MME地址）[678][ begin to excel fun:brsping ]value = 0(0x0)[ end to excel fun:brsping ]Ping : find no route for dest, send by default gateway [0xac1e8fc1]. send ping seq: 1...$$[678]PING===>reply from packetsize=36 time=14ms.——正常ping通时返回的时长[678]send ping seq: 2...[678]PING===>reply from packetsize=36 time=4ms.[678]send ping seq: 3...[678]PING===>reply from packetsize=36 time=3ms.[678]send ping seq: 4...[678]PING===>reply from packetsize=36 time=24ms.[678]Ping statistics for Packets: Sent = 4, Received = 4, Lost = 0(0% loss), Approximate round trip times in milli-seconds:Minimum = 3ms, Maximum = 24ms, Average = 11ms（ping核心网MME控制面地址结果，丢包率0%，证明基站到MME链路正常。
）brsping "" （ping核心网SGW地址）[678][ begin to excel fun:brsping ]value = 0(0x0)[ end to excel fun:brsping ]send ping seq: 1...$$[678]PING===>reply from packetsize=36 time < 1ms.[678]send ping seq: 2...[678]PING===>reply from packetsize=36 time < 1ms.[678]send ping seq: 3...[678]PING===>reply from packetsize=36 time=1ms.[678]send ping seq: 4...[678]PING===>reply from packetsize=36 time < 1ms.[678]Ping statistics for Packets: Sent = 4, Received = 4, Lost = 0(0% loss), Approximate round trip times in milli-seconds:Minimum = 0ms, Maximum = 1ms, Average = 0ms（ping核心网SGW用户面地址结果，丢包率0%，证明基站到SGW链路正常。
）通过以上步骤，排查基站到EPC的控制面MME和用户面SGW链路均正常。
3、Pad 到平台进程， showtcb 查看偶联状态，继续在平台进程中输入“showtcb”命令查看，偶联状态是否正常，若偶联异常，按照偶联断链告警指导手册处理。
$$showtcb[678][ begin to excel fun:showtcb ]=====Begin:Show Assoc TCB Info=====TCB info 0:偶联号0ULPID = 0, AssoID = 0, Checksum = 1, InstanceID = 0LocalPort = 6051, SourIP = VpnId = 31PeerPort = 6051, DestIP = VpnId = 31Association State = established（此处显示偶联状态，established标示偶联正常）CulTsnAcked = 24, NextTsnAssign = 25, LastRecvTSN = 61OutStandingSize = 0, PendingChkNum = 261888, MtuSize = 1500 TxReChkNum = 0TxStrmNum = 2, RxStrmNum = 2PeerVerifTag = 57, MyVerifTag = 17TCB info 11:偶联号11ULPID = 11, AssoID = 11, Checksum = 0, InstanceID = 11LocalPort = 36422, SourIP = VpnId = 31PeerPort = 36422, DestIP = VpnId = 31Association State = established（此处显示偶联状态，established标示偶联正常）CulTsnAcked = 01, NextTsnAssign = 02, LastRecvTSN = 0OutStandingSize = 0, PendingChkNum = 261888, MtuSize = 1500 TxReChkNum = 0TxStrmNum = 2, RxStrmNum = 2PeerVerifTag = 2, MyVerifTag = 77TCB info 12:偶连号12ULPID = 12, AssoID = 12, Checksum = 1, InstanceID = 12LocalPort = 36422, SourIP = VpnId = 31PeerPort = 36422, DestIP = VpnId = 31Association State = established（此处显示偶联状态，established标示偶联正常）CulTsnAcked = 01, NextTsnAssign = 02, LastRecvTSN = 40OutStandingSize = 0, PendingChkNum = 261888, MtuSize = 1500 TxReChkNum = 0TxStrmNum = 2, RxStrmNum = 2PeerVerifTag = 12, MyVerifTag = 77TCB info 13:偶连号13ULPID = 13, AssoID = 13, Checksum = 1, InstanceID = 13LocalPort = 36422, SourIP = VpnId = 31PeerPort = 36422, DestIP = VpnId = 31Association State = cookie_wait（此处显示偶联状态，cookie wait标示偶联不正常）CulTsnAcked = 0, NextTsnAssign = 05, LastRecvTSN = 0OutStandingSize = 0, PendingChkNum = 68, MtuSize = 0TxReChkNum = 0TxStrmNum = 2, RxStrmNum = 2PeerVerifTag = 0, MyVerifTag = 05TCB info 14:偶连号14ULPID = 14, AssoID = 14, Checksum = 1, InstanceID = 14LocalPort = 36422, SourIP = VpnId = 31PeerPort = 36422, DestIP = VpnId = 31Association State = cookie_wait（此处显示偶联状态，cookie wait标示偶联不正常）CulTsnAcked = 0, NextTsnAssign = 69, LastRecvTSN = 0OutStandingSize = 0, PendingChkNum = 68, MtuSize = 0TxReChkNum = 0TxStrmNum = 2, RxStrmNum = 2v1.0 可编辑可修改PeerVerifTag = 0, MyVerifTag = 69=====End:Show Assoc TCB Info=====value = 34(0x22)[ end to excel fun:showtcb ]$$exit（退出平台进程）ushell recv signo:0.quit debug and exit ushell!# exit（退出基站CC单板连接）关闭连接。