【正文】 sleep 400。當(dāng)需要從遠程主機上對跟蹤文件進行過程后處理或者，一段時間執(zhí)行記錄跟蹤數(shù)據(jù)，另一段時間用來對它進行過程后處理，這時這種脫機處理的方法就很有用處。一旦跟蹤過程終止，netpmon 命令就把它的通報送到標(biāo)準(zhǔn)輸出單元。 o 在預(yù)處理的基礎(chǔ)上通報因特網(wǎng)控制信息協(xié)議（ICMP）、傳輸控制協(xié)議（TCP）和用戶數(shù)據(jù)報協(xié)議（UDP）的統(tǒng)計量。netpmon 命令netpmon 命令使用跟蹤工具可以得到在一個時間間隔內(nèi)網(wǎng)絡(luò)操作的詳細內(nèi)容。驅(qū)動程序?qū)语@示了設(shè)備驅(qū)動程序為每一個適配器處理的信息包量。netstat r另一個和性能相關(guān)的參數(shù)項是人們定義的最大路徑發(fā)送單元（PMTU）的顯示。如果 TCP 發(fā)出一個信息包但沒有按時接收到 ACK 信號，就會生成重發(fā)超時的一個量。下面的例子顯示的是 tcp 協(xié)議的輸出： netstat p tcptcp: 63726 packets sent 34309 data packets (6482122 bytes) 198 data packets (161034 bytes) retransmitted 17437 ackonly packets (7882 delayed) 0 URG only packets 0 window probe packets 3562 window update packets 8220 control packets 71033 packets received 35989 acks (for 6444054 bytes) 2769 duplicate acks 0 acks for unsent data 47319 packets (19650209 bytes) received insequence 182 pletely duplicate packets (29772 bytes) 4 packets with some dup. data (1404 bytes duped) 2475 outoforder packets (49826 bytes) 0 packets (0 bytes) of data after window 0 window probes 800 window update packets 77 packets received after close 0 packets with bad hardware assisted checksum 0 discarded for bad checksums 0 discarded for bad header offset fields 0 connection request 3125 connection requests 1626 connection accepts 4731 connections established (including accepts) 5543 connections closed (including 31 drops) 62 embryonic connections dropped 38552 segments updated rtt (of 38862 attempts) 0 resends due to path MTU discovery 3 path MTU discovery terminations due to retransmits 553 retransmit timeouts 28 connections dropped by rexmit timeout 0 persist timeouts 464 keepalive timeouts 26 keepalive probes sent 1 connection dropped by keepalive 0 connections in timewait reused 0 delayed ACKs for SYN 0 delayed ACKs for FIN 0 send_and_disconnects所關(guān)心的統(tǒng)計信息是： * 發(fā)送的信息包 * 信息包 * 重新傳送的信息包 * 接收到的信息包 * 完全重復(fù)的信息包 * 重新傳送超時對于 TCP 統(tǒng)計信息，比較發(fā)送的信息包數(shù)和重發(fā)的信息包數(shù)。 * 由于無套接字導(dǎo)致的刪除 那些沒有打開端口的套接字所接收到的 UDP 數(shù)據(jù)報總數(shù)。對于發(fā)送的信息包和創(chuàng)建的段這也同樣適用。另一個原因可能是 mbuf 的不足造成的，這就要增加 thewall的參數(shù)值。一個空響應(yīng)表明，沒有要報告的數(shù)據(jù)。如果所請求大小的 mbuf 池為空，這個信息包就會被刪除。遇到的沖突次數(shù)超過了適配器上的重試次數(shù)。使用 IP 多點傳送可以把信息發(fā)送到一組主機上，而不需要對每一個工作組成員進行地址標(biāo)記和單獨發(fā)送信息。使用 SMIT 或者 chdev 命令可以改變隊列的大小。 netstat vETHERNET STATISTICS (ent0) :Device Type: IBM 10/100 Mbps Ethernet PCI Adapter (23100020)Hardware Address: 00:60:94:e9:29:18Elapsed Time: 9 days 19 hours 5 minutes 51 secondsTransmit Statistics: Receive Statistics: Packets: 0 Packets: 0Bytes: 0 Bytes: 0Interrupts: 0 Interrupts: 0Transmit Errors: 0 Receive Errors: 0Packets Dropped: 0 Packets Dropped: 0 Bad Packets: 0Max Packets on S/W Transmit Queue: 0S/W Transmit Queue Overflow: 0Current S/W+H/W Transmit Queue Length: 0Broadcast Packets: 0 Broadcast Packets: 0Multicast Packets: 0 Multicast Packets: 0No Carrier Sense: 0 CRC Errors: 0DMA Underrun: 0 DMA Overrun: 0Lost CTS Errors: 0 Alignment Errors: 0Max Collision Errors: 0 No Resource Errors: 0Late Collision Errors: 0 Receive Collision Errors: 0Deferred: 0 Packet Too Short Errors: 0SQE Test: 0 Packet Too Long Errors: 0Timeout Errors: 0 Packets Discarded by Adapter: 0Single Collision Count: 0 Receiver Start Count: 0Multiple Collision Count: 0Current HW Transmit Queue Length: 0General Statistics:No mbuf Errors: 0Adapter Reset Count: 0Driver Flags: Up Broadcast Running Simplex 64BitSupport PrivateSegmentIBM 10/100 Mbps Ethernet PCI Adapter Specific Statistics:Chip Version: 25RJ45 Port Link Status : downMedia Speed Selected: 10 Mbps Half DuplexMedia Speed Running: UnknownReceive Pool Buffer Size: 384Free Receive Pool Buffers: 128No Receive Pool Buffer Errors: 0Inter Packet Gap: 96Adapter Restarts due to IOCTL mands: 0Packets with Transmit collisions: 1 collisions: 0 6 collisions: 0 11 collisions: 0 2 collisions: 0 7 collisions: 0 12 collisions: 0 3 collisions: 0 8 collisions: 0 13 collisions: 0 4 collisions: 0 9 collisions: 0 14 collisions: 0 5 collisions: 0 10 collisions: 0 15 collisions: 0Excessive deferral errors: 0x0TOKENRING STATISTICS (tok0) :Device Type: IBM PCI Tokenring Adapter (14103e00)Hardware Address: 00:20:35:7a:12:8aElapsed Time: 29 days 18 hours 3 minutes 47 secondsTransmit Statistics: Receive Statistics: Packets: 1355364 Packets: 55782254Bytes: 791555422 Bytes: 6679991641Interrupts: 902315 Interrupts: 55782192T