监视网络接口TCP状态信息数据有多种工具或命令。下面举例一些：

nstat命令

# nstat
#kernel
IpInReceives                    9733104            0.0
IpInDelivers                    9733102            0.0
IpOutRequests                   9058593            0.0
IcmpInErrors                    2147               0.0
IcmpInCsumErrors                1143               0.0
IcmpInDestUnreachs              2                  0.0
IcmpInTimeExcds                 1361               0.0
IcmpInParmProbs                 56                 0.0
IcmpInRedirects                 1                  0.0
IcmpInEchoReps                  701                0.0
IcmpInTimestamps                26                 0.0
IcmpOutErrors                   750                0.0
IcmpOutTimeExcds                23                 0.0
IcmpOutEchoReps                 26                 0.0
IcmpOutTimestamps               701                0.0
IcmpMsgInType0                  26                 0.0
IcmpMsgInType3                  1361               0.0
IcmpMsgInType4                  1                  0.0
IcmpMsgInType8                  701                0.0
IcmpMsgInType11                 56                 0.0
IcmpMsgOutType0                 701                0.0
IcmpMsgOutType3                 23                 0.0
IcmpMsgOutType8                 26                 0.0
TcpActiveOpens                  678940             0.0
TcpPassiveOpens                 910289             0.0
TcpAttemptFails                 58018              0.0
TcpEstabResets                  14608              0.0
TcpInSegs                       9686518            0.0
TcpOutSegs                      9038288            0.0
TcpRetransSegs                  6700               0.0
TcpInErrs                       47                 0.0
TcpOutRsts                      67249              0.0
UdpInDatagrams                  44409              0.0
UdpNoPorts                      23                 0.0
UdpOutDatagrams                 44441              0.0
Ip6InReceives                   6                  0.0
Ip6InNoRoutes                   6                  0.0
Ip6OutRequests                  9                  0.0
Ip6OutNoRoutes                  3948               0.0
Ip6OutMcastPkts                 14                 0.0
Ip6InOctets                     432                0.0
Ip6OutOctets                    612                0.0
Ip6OutMcastOctets               992                0.0
Ip6InNoECTPkts                  6                  0.0
Icmp6OutMsgs                    9                  0.0
Icmp6OutRouterSolicits          3                  0.0
Icmp6OutNeighborSolicits        1                  0.0
Icmp6OutMLDv2Reports            5                  0.0
Icmp6OutType133                 3                  0.0
Icmp6OutType135                 1                  0.0
Icmp6OutType143                 5                  0.0
TcpExtSyncookiesFailed          140                0.0
TcpExtEmbryonicRsts             704                0.0
TcpExtPruneCalled               23                 0.0
TcpExtTW                        615681             0.0
TcpExtPAWSEstab                 20                 0.0
TcpExtDelayedACKs               52123              0.0
TcpExtDelayedACKLocked          44                 0.0
TcpExtDelayedACKLost            1518               0.0
TcpExtListenDrops               32                 0.0
TcpExtTCPPrequeued              19258              0.0
TcpExtTCPDirectCopyFromBacklog  45185              0.0
TcpExtTCPDirectCopyFromPrequeue 394312             0.0
TcpExtTCPHPHits                 943072             0.0
TcpExtTCPHPHitsToUser           3478               0.0
TcpExtTCPPureAcks               3242625            0.0
TcpExtTCPHPAcks                 547259             0.0
TcpExtTCPSackRecovery           650                0.0
TcpExtTCPFACKReorder            1                  0.0
TcpExtTCPSACKReorder            8                  0.0
TcpExtTCPTSReorder              23                 0.0
TcpExtTCPFullUndo               1                  0.0
TcpExtTCPPartialUndo            23                 0.0
TcpExtTCPDSACKUndo              1                  0.0
TcpExtTCPLossUndo               854                0.0
TcpExtTCPLostRetransmit         162                0.0
TcpExtTCPSackFailures           135                0.0
TcpExtTCPLossFailures           18                 0.0
TcpExtTCPFastRetrans            1517               0.0
TcpExtTCPForwardRetrans         104                0.0
TcpExtTCPSlowStartRetrans       172                0.0
TcpExtTCPTimeouts               2764               0.0
TcpExtTCPLossProbes             5201               0.0
TcpExtTCPLossProbeRecovery      2858               0.0
TcpExtTCPSackRecoveryFail       74                 0.0
TcpExtTCPRcvCollapsed           460                0.0
TcpExtTCPDSACKOldSent           1645               0.0
TcpExtTCPDSACKOfoSent           21                 0.0
TcpExtTCPDSACKRecv              879                0.0
TcpExtTCPAbortOnData            4314               0.0
TcpExtTCPAbortOnClose           346                0.0
TcpExtTCPAbortOnTimeout         186                0.0
TcpExtTCPDSACKIgnoredNoUndo     615                0.0
TcpExtTCPSpuriousRTOs           95                 0.0
TcpExtTCPSackShifted            402                0.0
TcpExtTCPSackMerged             2048               0.0
TcpExtTCPSackShiftFallback      2592               0.0
TcpExtTCPRcvCoalesce            145162             0.0
TcpExtTCPOFOQueue               36672              0.0
TcpExtTCPOFOMerge               21                 0.0
TcpExtTCPChallengeACK           329                0.0
TcpExtTCPSYNChallenge           47                 0.0
IpExtInNoRoutes                 2                  0.0
IpExtInOctets                   1568628267         0.0
IpExtOutOctets                  1158526375         0.0
IpExtInNoECTPkts                9828130            0.0
IpExtInECT0Pkts                 10                 0.0
IpExtInCEPkts                   3                  0.0

ss命令

# ss -s
Total: 319 (kernel 752)
TCP:   187 (estab 114, closed 58, orphaned 0, synrecv 0, timewait 58/0), ports 0

Transport Total     IP        IPv6
*         752       -         -        
RAW       0         0         0        
UDP       3         2         1        
TCP       129       113       16       
INET      132       115       17       
FRAG      0         0         0

netstat命令

# netstat -i
Kernel Interface table
Iface   MTU Met   RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0       9001 0   2194916      0      0 0       1424609      0      0      0 BMRU
lo        65536 0   7670598      0      0 0       7670598      0      0      0 LRU

# netstat -s
Ip:
    9743496 total packets received
    0 forwarded
    0 incoming packets discarded
    9743494 incoming packets delivered
    9068146 requests sent out
Icmp:
    2147 ICMP messages received
    1143 input ICMP message failed.
    InCsumErrors: 2
    ICMP input histogram:
        destination unreachable: 1361
        timeout in transit: 56
        source quenches: 1
        echo requests: 701
        echo replies: 26
    750 ICMP messages sent
    0 ICMP messages failed
    ICMP output histogram:
        destination unreachable: 23
        echo request: 26
        echo replies: 701
IcmpMsg:
        InType0: 26
        InType3: 1361
        InType4: 1
        InType8: 701
        InType11: 56
        OutType0: 701
        OutType3: 23
        OutType8: 26
Tcp:
    679665 active connections openings
    911387 passive connection openings
    58018 failed connection attempts
    14608 connection resets received
    118 connections established
    9696894 segments received
    9047825 segments send out
    6700 segments retransmited
    47 bad segments received.
    67249 resets sent
Udp:
    44425 packets received
    23 packets to unknown port received.
    0 packet receive errors
    44457 packets sent
UdpLite:
TcpExt:
    140 invalid SYN cookies received
    704 resets received for embryonic SYN_RECV sockets
    23 packets pruned from receive queue because of socket buffer overrun
    616402 TCP sockets finished time wait in fast timer
    20 packets rejects in established connections because of timestamp
    52124 delayed acks sent
    45 delayed acks further delayed because of locked socket
    Quick ack mode was activated 1519 times
    32 SYNs to LISTEN sockets dropped
    19258 packets directly queued to recvmsg prequeue.
    45185 bytes directly in process context from backlog
    394312 bytes directly received in process context from prequeue
    943942 packet headers predicted
    3478 packets header predicted and directly queued to user
    3246338 acknowledgments not containing data payload received
    547737 predicted acknowledgments
    650 times recovered from packet loss by selective acknowledgements
    Detected reordering 1 times using FACK
    Detected reordering 8 times using SACK
    Detected reordering 23 times using time stamp
    1 congestion windows fully recovered without slow start
    23 congestion windows partially recovered using Hoe heuristic
    1 congestion windows recovered without slow start by DSACK
    854 congestion windows recovered without slow start after partial ack
    TCPLostRetransmit: 162
    135 timeouts after SACK recovery
    18 timeouts in loss state
    1517 fast retransmits
    104 forward retransmits
    172 retransmits in slow start
    2764 other TCP timeouts
    TCPLossProbes: 5202
    TCPLossProbeRecovery: 2859
    74 SACK retransmits failed
    460 packets collapsed in receive queue due to low socket buffer
    1646 DSACKs sent for old packets
    21 DSACKs sent for out of order packets
    879 DSACKs received
    4314 connections reset due to unexpected data
    346 connections reset due to early user close
    186 connections aborted due to timeout
    TCPDSACKIgnoredNoUndo: 615
    TCPSpuriousRTOs: 95
    TCPSackShifted: 402
    TCPSackMerged: 2048
    TCPSackShiftFallback: 2592
    TCPRcvCoalesce: 145187
    TCPOFOQueue: 36673
    TCPOFOMerge: 21
    TCPChallengeACK: 329
    TCPSYNChallenge: 47
IpExt:
    InNoRoutes: 2
    InOctets: 1570012766
    OutOctets: 1159491497
    InNoECTPkts: 9838700
    InECT0Pkts: 10
    InCEPkts: 3

ip命令

# ip -s link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    RX: bytes  packets  errors  dropped overrun mcast   
    883395575  7672258  0       0       0       0      
    TX: bytes  packets  errors  dropped carrier collsns 
    883395575  7672258  0       0       0       0      
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9001 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
    link/ether 02:7a:7d:d2:f7:21 brd ff:ff:ff:ff:ff:ff
    RX: bytes  packets  errors  dropped overrun mcast   
    694754381  2197268  0       0       0       0      
    TX: bytes  packets  errors  dropped carrier collsns 
    296980409  1425257  0       0       0       0

sar命令

# sar -n DEV 1 
Linux 3.13.0-48-generic (beta)  2015年08月17日  _x86_64_        (4 CPU)

14时46分54秒     IFACE   rxpck/s   txpck/s    rxkB/s    txkB/s   rxcmp/s   txcmp/s  rxmcst/s   %ifutil
14时46分55秒      eth0     12.00      5.00      0.97      1.18      0.00      0.00      0.00      0.00
14时46分55秒        lo     10.00     10.00      1.00      1.00      0.00      0.00      0.00      0.00

14时46分55秒     IFACE   rxpck/s   txpck/s    rxkB/s    txkB/s   rxcmp/s   txcmp/s  rxmcst/s   %ifutil
14时46分56秒      eth0      1.00      1.00      0.05      0.47      0.00      0.00      0.00      0.00
14时46分56秒        lo     16.00     16.00      2.17      2.17      0.00      0.00      0.00      0.00

14时46分56秒     IFACE   rxpck/s   txpck/s    rxkB/s    txkB/s   rxcmp/s   txcmp/s  rxmcst/s   %ifutil
14时46分57秒      eth0      5.00      3.00      0.26      0.61      0.00      0.00      0.00      0.00
14时46分57秒        lo     10.00     10.00      1.00      1.00      0.00      0.00      0.00      0.00

还有其它工具如nload，iftop等等，不一一列举了。