nstat命令和rtacct命令是一个简单的监视内核的SNMP计数器和网络接口状态的实用工具。
语法
nstat/rtacct(选项)
选项
-h：显示帮助信息；
-V：显示指令版本信息；
-z：显示0计数器；
-r：清零历史统计；
-n：不显示任何内容，仅更新历史；
-a：显示计数器的绝对值；
-s：不更新历史；
-d：以守护进程的方式运行本指令。
实例
[root@localhost ~]# nstat
#kernel
#kernel IpInReceives 15766482 0.0 IpInDelivers 15538384 0.0 IpOutRequests 9746938 0.0 IpReasmReqds 8 0.0 IpReasmOKs 4 0.0 IcmpInErrors 28701 0.0 IcmpInDestUnreachs 405 0.0 IcmpInTimeExcds 1812 0.0 IcmpInParmProbs 173 0.0 IcmpInEchoReps 26613 0.0 IcmpInTimestamps 100 0.0 IcmpOutErrors 27065 0.0 IcmpOutTimeExcds 331 0.0 IcmpOutEchoReps 121 0.0 IcmpOutTimestamps 26613 0.0 IcmpMsgInType0 100 0.0 IcmpMsgInType3 1812 0.0 IcmpMsgInType8 26613 0.0 IcmpMsgInType11 173 0.0 IcmpMsgOutType0 26613 0.0 IcmpMsgOutType3 331 0.0 IcmpMsgOutType8 121 0.0 TcpActiveOpens 24760 0.0 TcpPassiveOpens 573863 0.0 TcpAttemptFails 18347 0.0 TcpEstabResets 67353 0.0 TcpInSegs 15324047 0.0 TcpOutSegs 9296351 0.0 TcpRetransSegs 118479 0.0 TcpInErrs 560 0.0 TcpOutRsts 15269 0.0 UdpInDatagrams 185300 0.0 UdpNoPorts 331 0.0 UdpOutDatagrams 305043 0.0 TcpExtSyncookiesFailed 14328 0.0 TcpExtEmbryonicRsts 15116 0.0 TcpExtOutOfWindowIcmps 79 0.0 TcpExtTW 158436 0.0 TcpExtDelayedACKs 123597 0.0 TcpExtDelayedACKLocked 1087 0.0 TcpExtDelayedACKLost 55670 0.0 TcpExtTCPPrequeued 288438 0.0 TcpExtTCPDirectCopyFromBacklog 11229302 0.0 TcpExtTCPDirectCopyFromPrequeue 669949 0.0 TcpExtTCPHPHits 7539804 0.0 TcpExtTCPHPHitsToUser 7700 0.0 TcpExtTCPPureAcks 2743573 0.0 TcpExtTCPHPAcks 1742135 0.0 TcpExtTCPRenoRecovery 51 0.0 TcpExtTCPSackRecovery 15556 0.0 TcpExtTCPSACKReneging 13 0.0 TcpExtTCPFACKReorder 199 0.0 TcpExtTCPSACKReorder 63 0.0 TcpExtTCPTSReorder 220 0.0 TcpExtTCPFullUndo 213 0.0 TcpExtTCPPartialUndo 868 0.0 TcpExtTCPDSACKUndo 2831 0.0 TcpExtTCPLossUndo 2320 0.0 TcpExtTCPLoss 22652 0.0 TcpExtTCPLostRetransmit 2 0.0 TcpExtTCPRenoFailures 26 0.0 TcpExtTCPSackFailures 4765 0.0 TcpExtTCPLossFailures 2155 0.0 TcpExtTCPFastRetrans 28636 0.0 TcpExtTCPForwardRetrans 3341 0.0 TcpExtTCPSlowStartRetrans 25393 0.0 TcpExtTCPTimeouts 28215 0.0 TcpExtTCPRenoRecoveryFail 26 0.0 TcpExtTCPSackRecoveryFail 2892 0.0 TcpExtTCPDSACKOldSent 55916 0.0 TcpExtTCPDSACKOfoSent 299 0.0 TcpExtTCPDSACKRecv 11680 0.0 TcpExtTCPDSACKOfoRecv 35 0.0 TcpExtTCPAbortOnData 1193 0.0 TcpExtTCPAbortOnClose 14 0.0 TcpExtTCPAbortOnTimeout 3041 0.0