标签：systems 而不是 list 常用 网络路由 emd localhost ted reac
统计指定的文件中的字节数、字数、行数，并将统计结果显示输出。如果没有给出文件名，则从标准输入读取。wc同时也给出所指文件的总统计数
语法：wc [选项] [文件名]
-c：统计字节数；
-l：统计行数；
-m：统计字符数。这个标志不能与-c一起使用；
-w：统计字数。一个字被定义为空白、跳格或者换行字符分割的字符串；
-L：打印最长行的长度
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[root@localhost wc]# cat test.txthnlinuxpeida.cnblogs.comubuntuubuntu linuxredhatRedhatlinuxmint[root@localhost wc]# wc test.txt 7 8 76 test.txt[root@localhost wc]# wc -l test.txt7 test.txt[root@localhost wc]# wc -c test.txt76 test.txt[root@localhost wc]# wc -w test.txt8 test.txt[root@localhost wc]# wc -m test.txt76 test.txt[root@localhost wc]# wc -L test.txt18 test.txt[root@localhost wc]# |
uptime命令能够打印系统运行了多长时间和系统平均负载。uptime命令可以显示的信息依次是：现在时间、系统已经运行了多长时间、目前有多少登录用户、系统过去的1分钟、5分钟和15分钟内的平均负载。
语法：uptime [选项]
-V：显示指令的版本信息
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[root@localhost wc]# uptime -Vuptime from procps-ng 3.3.10[root@localhost wc]# |
使用uptime命令查看系统负载：
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[root@localhost wc]# uptime 22:16:12 up 4:26, 1 user, load average: 0.08, 0.04, 0.05[root@localhost wc]# |
显示内容说明：
22:16:12//系统当前时间
up 4:26//主机已经运行时间，时间越大，说明你的机器越稳定
1 user//用户连接数，是总连接数而不是用户数
load average: 0.08, 0.04, 0.05//系统平均负载，统计最近1,5,15分钟的系统平均负载
cut命令从文件的每一行剪切字节、字符和字段并将这些字节、字符和字段写入标准输出。
语法：cut [-bn] [file] 或 cut [-c] [file] 或 cut [-df] [file]
如果不指定file参数，cut命令将读取标准输入。必须制定-b、-c或-f标志之一。
-b：已字节为单位进行分割。这些字节位置将忽略多字节字符边界，除非也制定了-n标志。
-c：已字符为单位进行分割。
-d：自定义分隔符，默认为制表符。
-f：与-d一起使用，制定显示哪个区域。
-n：取消分割多字节字符。仅和-b标志一起使用。如果字符的最后一个字节落在由-b标志的List参数指定的<br/>范围之内，该字符将被写出；否则，该字符被排除。
cut命令可将一串字符作为列来显示，字符字段的记法：
N-：从第N个字节、字符、字段到结尾。
N-M：从第N个字节、字符、字段到第M个（包括M在内）字节、字符、字段。
-M：从第1个字节、字符、字段到第M个（包括M在内）字节、字符、字段。
以/etc/passwd的前5行内容为例：
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[root@localhost wc]# head -n 5 /etc/passwdroot:x:0:0:root:/root:/bin/bashbin:x:1:1:bin:/bin:/sbin/nologindaemon:x:2:2:daemon:/sbin:/sbin/nologinadm:x:3:4:adm:/var/adm:/sbin/nologinlp:x:4:7:lp:/var/spool/lpd:/sbin/nologin[root@localhost wc]# |
截取用户名：-d来设置分隔符为“:”，然后用-f来设置截取第一个域：
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[root@localhost wc]# head -n 5 /etc/passwd | cut -d ‘:‘ -f 1rootbindaemonadmlp[root@localhost wc]# |
截取第1,3到5字段：
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[root@localhost wc]# head -n 5 /etc/passwd | cut -d ‘:‘ -f 1,3-5root:0:0:rootbin:1:1:bindaemon:2:2:daemonadm:3:4:admlp:4:7:lp[root@localhost wc]# |
截取1到3个字符：
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[root@localhost wc]# head -n 5 /etc/passwd | cut -c 1-3roobindaeadmlp:[root@localhost wc]# |
截取前2个字符：
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[root@localhost wc]# head -n 5 /etc/passwd | cut -c -2robidaadlp[root@localhost wc]# |
截取第5个字符开始到结尾：
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[root@localhost wc]# head -n 5 /etc/passwd | cut -c 5-:x:0:0:root:/root:/bin/bashx:1:1:bin:/bin:/sbin/nologinon:x:2:2:daemon:/sbin:/sbin/nologinx:3:4:adm:/var/adm:/sbin/nologin:4:7:lp:/var/spool/lpd:/sbin/nologin[root@localhost wc]# |
netstat是一个告诉我们系统中所有tcp/udp/unix socket连接状态的命令行工具。它会列出所有已连接或等待连接状态的连接。该工具在识别某个应用监听哪个端口时特别有用，我们也能用它来判断某个应用是否正常的在监听某个端口。
netstat命令还能显示其他各种各样的网络相关信息，例如路由表，网卡统计信息，虚假连接以及多播成员等。
1）、检查所有的连接
使用a选项可以列出系统中的所有连接。
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[root@localhost wc]# netstat -aActive Internet connections (servers and established)Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:ssh 0.0.0.0:* LISTEN tcp 0 0 localhost:smtp 0.0.0.0:* LISTEN tcp 0 52 localhost.localdoma:ssh 10.0.30.1:lnvmaps ESTABLISHEDtcp6 0 0 [::]:mysql [::]:* LISTEN tcp6 0 0 [::]:ssh [::]:* LISTEN tcp6 0 0 localhost:smtp [::]:* LISTEN raw6 0 0 [::]:ipv6-icmp [::]:* 7 Active UNIX domain sockets (servers and established)Proto RefCnt Flags Type State I-Node Pathunix 2 [ ACC ] STREAM LISTENING 13568 /run/lvm/lvmetad.socketunix 2 [ ] DGRAM 13571 /run/systemd/shutdowndunix 3 [ ] DGRAM 8710 /run/systemd/notifyunix 2 [ ] DGRAM 8712 /run/systemd/cgroups-agentunix 2 [ ACC ] STREAM LISTENING 21355 public/showqunix 2 [ ACC ] STREAM LISTENING 8730 /run/systemd/journal/stdoutunix 5 [ ] DGRAM 8733 /run/systemd/journal/socket |
这会显示系统所有的tcp、udp以及unix连接。
2）、检查所有tcp/udp/unix socket连接
使用t选项只列出tcp连接。
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[root@localhost wc]# netstat -atActive Internet connections (servers and established)Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:ssh 0.0.0.0:* LISTEN tcp 0 0 localhost:smtp 0.0.0.0:* LISTEN tcp 0 52 localhost.localdoma:ssh 10.0.30.1:lnvmaps ESTABLISHEDtcp6 0 0 [::]:mysql [::]:* LISTEN tcp6 0 0 [::]:ssh [::]:* LISTEN tcp6 0 0 localhost:smtp [::]:* LISTEN [root@localhost wc]# |
类似的，使用u选项只列出udp连接。
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[root@localhost wc]# netstat -auActive Internet connections (servers and established)Proto Recv-Q Send-Q Local Address Foreign Address State [root@localhost wc]# |
使用x选项只列出unix socket连接。
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[root@localhost wc]# netstat -axActive UNIX domain sockets (servers and established)Proto RefCnt Flags Type State I-Node Pathunix 2 [ ACC ] STREAM LISTENING 13568 /run/lvm/lvmetad.socketunix 2 [ ] DGRAM 13571 /run/systemd/shutdowndunix 3 [ ] DGRAM 8710 /run/systemd/notifyunix 2 [ ] DGRAM 8712 /run/systemd/cgroups-agentunix 2 [ ACC ] STREAM LISTENING 21355 public/showqunix 2 [ ACC ] STREAM LISTENING 8730 /run/systemd/journal/stdoutunix 5 [ ] DGRAM 8733 /run/systemd/journal/socketunix 12 [ ] DGRAM 8735 /dev/logunix 2 [ ACC ] SEQPACKET LISTENING 13622 /run/udev/controlunix 2 [ ACC ] STREAM LISTENING 21620 /tmp/mysql.sockunix 2 [ ACC ] STREAM LISTENING 21330 private/traceunix 2 [ ACC ] STREAM LISTENING 21337 private/verifyunix 2 [ ACC ] STREAM LISTENING 21343 private/proxymap |
3）、同时列出ID/进程名称
使用p选项可以列出连接的同时也显示PID或者进程名称，而且它还能与其他选项连用。
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[root@localhost wc]# netstat -apActive Internet connections (servers and established)Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:ssh 0.0.0.0:* LISTEN 992/sshd tcp 0 0 localhost:smtp 0.0.0.0:* LISTEN 1563/master tcp 0 52 localhost.localdoma:ssh 10.0.30.1:lnvmaps ESTABLISHED 1813/sshd: root@ptstcp6 0 0 [::]:mysql [::]:* LISTEN 1631/mysqld tcp6 0 0 [::]:ssh [::]:* LISTEN 992/sshd tcp6 0 0 localhost:smtp [::]:* LISTEN 1563/master raw6 0 0 [::]:ipv6-icmp [::]:* 7 686/NetworkManager Active UNIX domain sockets (servers and established)Proto RefCnt Flags Type State I-Node PID/Program name Pathunix 2 [ ACC ] STREAM LISTENING 13568 1/systemd /run/lvm/lvmetad.socketunix 2 [ ] DGRAM 13571 1/systemd /run/systemd/shutdowndunix 3 [ ] DGRAM 8710 1/systemd /run/systemd/notifyunix 2 [ ] DGRAM 8712 1/systemd /run/systemd/cgroups-agentunix 2 [ ACC ] STREAM LISTENING 21355 1563/master public/showqunix 2 [ ACC ] STREAM LISTENING 8730 1/systemd /run/systemd/journal/stdoutunix 5 [ ] DGRAM 8733 1/systemd /run/systemd/journal/socketunix 12 [ ] DGRAM 8735 1/systemd /dev/logunix 2 [ ACC ] SEQPACKET LISTENING 13622 1/systemd /run/udev/controlunix 2 [ ACC ] STREAM LISTENING 21620 1631/mysqld /tmp/mysql.sockunix 2 [ ACC ] STREAM LISTENING 21330 1563/master private/traceunix 2 [ ACC ] STREAM LISTENING 21337 1563/master private/verifyunix 2 [ ACC ] STREAM LISTENING 21343 1563/master private/proxymapunix 2 [ ACC ] STREAM LISTENING 21346 1563/master private/proxywriteunix 2 [ ACC ] STREAM LISTENING 21349 1563/master private/smtpunix 2 [ ACC ] STREAM LISTENING 21352 1563/master private/relayunix 2 [ ACC ] STREAM LISTENING 21358 1563/master private/errorunix 2 [ ACC ] STREAM LISTENING 21361 1563/master private/retry |
4）、列出端口号而不是服务名
使用n选项可以加快输出，它不会执行任何反向查询，而是直接输出数字。由于无需查询，因此结果输出会很快。
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[root@localhost wc]# netstat -anActive Internet connections (servers and established)Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN tcp 0 52 10.0.30.102:22 10.0.30.1:2284 ESTABLISHEDtcp6 0 0 :::3306 :::* LISTEN tcp6 0 0 :::22 :::* LISTEN tcp6 0 0 ::1:25 :::* LISTEN raw6 0 0 :::58 :::* 7 Active UNIX domain sockets (servers and established)Proto RefCnt Flags Type State I-Node Pathunix 2 [ ACC ] STREAM LISTENING 13568 /run/lvm/lvmetad.socketunix 2 [ ] DGRAM 13571 /run/systemd/shutdowndunix 3 [ ] DGRAM 8710 /run/systemd/notifyunix 2 [ ] DGRAM 8712 /run/systemd/cgroups-agentunix 2 [ ACC ] STREAM LISTENING 21355 public/showqunix 2 [ ACC ] STREAM LISTENING 8730 /run/systemd/journal/stdoutunix 5 [ ] DGRAM 8733 /run/systemd/journal/socketunix 12 [ ] DGRAM 8735 /dev/logunix 2 [ ACC ] SEQPACKET LISTENING 13622 /run/udev/controlunix 2 [ ACC ] STREAM LISTENING 21620 /tmp/mysql.sockunix 2 [ ACC ] STREAM LISTENING 21330 private/traceunix 2 [ ACC ] STREAM LISTENING 21337 private/verifyunix 2 [ ACC ] STREAM LISTENING 21343 private/proxymapunix 2 [ ACC ] STREAM LISTENING 21346 private/proxywriteunix 2 [ ACC ] STREAM LISTENING 21349 private/smtpunix 2 [ ACC ] STREAM LISTENING 21352 private/relay |
5）、只输出监听端口
使用l选项只输出监听端口。它不能与a选项连用，因为a会输出所有端口。
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[root@localhost wc]# netstat -lActive Internet connections (only servers)Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:ssh 0.0.0.0:* LISTEN tcp 0 0 localhost:smtp 0.0.0.0:* LISTEN tcp6 0 0 [::]:mysql [::]:* LISTEN tcp6 0 0 [::]:ssh [::]:* LISTEN tcp6 0 0 localhost:smtp [::]:* LISTEN raw6 0 0 [::]:ipv6-icmp [::]:* 7 Active UNIX domain sockets (only servers)Proto RefCnt Flags Type State I-Node Pathunix 2 [ ACC ] STREAM LISTENING 13568 /run/lvm/lvmetad.socketunix 2 [ ACC ] STREAM LISTENING 21355 public/showqunix 2 [ ACC ] STREAM LISTENING 8730 /run/systemd/journal/stdoutunix 2 [ ACC ] SEQPACKET LISTENING 13622 /run/udev/controlunix 2 [ ACC ] STREAM LISTENING 21620 /tmp/mysql.sockunix 2 [ ACC ] STREAM LISTENING 21330 private/traceunix 2 [ ACC ] STREAM LISTENING 21337 private/verifyunix 2 [ ACC ] STREAM LISTENING 21343 private/proxymapunix 2 [ ACC ] STREAM LISTENING 21346 private/proxywriteunix 2 [ ACC ] STREAM LISTENING 21349 private/smtpunix 2 [ ACC ] STREAM LISTENING 21352 private/relayunix 2 [ ACC ] STREAM LISTENING 21358 private/errorunix 2 [ ACC ] STREAM LISTENING 21361 private/retryunix 2 [ ACC ] STREAM LISTENING 21364 private/discardunix 2 [ ACC ] STREAM LISTENING 21367 private/localunix 2 [ ACC ] STREAM LISTENING 21370 private/virtualunix 2 [ ACC ] STREAM LISTENING 21373 private/lmtpunix 2 [ ACC ] STREAM LISTENING 21377 private/anvilunix 2 [ ACC ] STREAM LISTENING 21380 private/scacheunix 2 [ ACC ] STREAM LISTENING 13436 /run/systemd/privateunix 2 [ ACC ] STREAM LISTENING 16805 /run/dbus/system_bus_socketunix 2 [ ACC ] STREAM LISTENING 21297 public/pickupunix 2 [ ACC ] STREAM LISTENING 21302 public/cleanupunix 2 [ ACC ] STREAM LISTENING 21305 public/qmgrunix 2 [ ACC ] STREAM LISTENING 21340 public/flushunix 2 [ ACC ] STREAM LISTENING 21309 private/tlsmgrunix 2 [ ACC ] STREAM LISTENING 21321 private/rewriteunix 2 [ ACC ] STREAM LISTENING 21324 private/bounceunix 2 [ ACC ] STREAM LISTENING 21327 private/deferunix 2 [ ACC ] STREAM LISTENING 13761 /run/lvm/lvmpolld.socketunix 2 [ ACC ] STREAM LISTENING 17657 /var/run/vmware/guestServicePipe[root@localhost wc]# |
6）、输出网络状态
使用s选项输出每个协议的统计信息，包括接收/发送的包数量。
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[root@localhost wc]# netstat -sIp: 4688 total packets received 0 forwarded 0 incoming packets discarded 4408 incoming packets delivered 4110 requests sent outIcmp: 818 ICMP messages received 409 input ICMP message failed. ICMP input histogram: destination unreachable: 818 818 ICMP messages sent 0 ICMP messages failed ICMP output histogram: destination unreachable: 818IcmpMsg: InType3: 818 OutType3: 818Tcp: 409 active connections openings 1 passive connection openings 409 failed connection attempts 0 connection resets received 1 connections established 3574 segments received 2888 segments send out 409 segments retransmited 0 bad segments received. 0 resets sentUdp: 16 packets received 0 packets to unknown port received. 0 packet receive errors 16 packets sent 0 receive buffer errors 0 send buffer errorsUdpLite:TcpExt: 14 delayed acks sent 1 delayed acks further delayed because of locked socket 1041 packet headers predicted 556 acknowledgments not containing data payload received 1386 predicted acknowledgments 409 other TCP timeouts TCPRcvCoalesce: 1 TCPSpuriousRtxHostQueues: 760 TCPSynRetrans: 409 TCPOrigDataSent: 2440IpExt: InBcastPkts: 280 InOctets: 374032 OutOctets: 465867 InBcastOctets: 27427 InNoECTPkts: 4688[root@localhost wc]# |
7）、输出网卡状态
使用i选项只显示网卡的统计信息。
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[root@localhost wc]# netstat -iKernel Interface tableIface MTU RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flgens33 1500 4152 0 0 0 5224 0 0 0 BMRUlo 65536 822 0 0 0 822 0 0 0 LRU[root@localhost wc]# |
8）、显示多播组信息
使用g选项输出IPV4以及IPV6的多播信息。
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[root@localhost wc]# netstat -gIPv6/IPv4 Group MembershipsInterface RefCnt Group--------------- ------ ---------------------lo 1 all-systems.mcast.netens33 1 all-systems.mcast.netlo 1 ff02::1lo 1 ff01::1 |
9）、显示网络路由信息
使用r选项输出网络路由信息。
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[root@localhost wc]# netstat -rKernel IP routing tableDestination Gateway Genmask Flags MSS Window irtt Ifacedefault gateway 0.0.0.0 UG 0 0 0 ens3310.0.30.0 0.0.0.0 255.255.254.0 U 0 0 0 ens33[root@localhost wc]# |
10）、持续输出
使用c选项持续输出信息。
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[root@localhost wc]# netstat -c |
标签：systems 而不是 list 常用 网络路由 emd localhost ted reac
原文地址：https://www.cnblogs.com/codebuglife/p/12550855.html
