Operation and maintenance engineers in the process of configuration often need to get the IP address of the target server network card, which way to get more convenient, bloggers today take everyone to use the Linux text Three Musketeers to obtain the IP address of the network card, and finally we will compare.
Lab Environment:
System: CentOS 7.2
Network card number: Dual NIC
Linux text The Three Musketeers grep
Get the IP address in the ifconfig output
Ifconfig | Egrep-o "\< ([1-9]|[ 1-9][0-9]|1[0-9][0-9]|2[0-1][0-9]|22[0-3]) \>. (\< ([0-9]|[ 1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5]) \>\.) {2}\< ([0-9]|[ 1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-4]) \> "
Get the IP address in the network card configuration file
Egrep-o "\< ([1-9]|[ 1-9][0-9]|1[0-9][0-9]|2[0-1][0-9]|22[0-3]) \>. (\< ([0-9]|[ 1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5]) \>\.) {2}\< ([0-9]|[ 1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-4]) \> "/etc/sysconfig/network-scripts/ifcfg-eth*
/etc/sysconfig/network-scripts/ifcfg-eth0:10.29.88.57
/etc/sysconfig/network-scripts/ifcfg-eth1:118.190.87.211
Advantages:
The matching rule is strong, can obtain the IP address in the ifconfig output, and can obtain the IP address in the network card configuration file, the matching rule does not need to make any changes.
Disadvantages:
Command lengthy, not easy to remember
the Three Musketeers of the Linux text sed
Get the IP address in the ifconfig output
Ifconfig | Sed-rn ' s/^.*inet (. *) net.*/\1/p '
Get the IP address in the network card configuration file
Sed-rn ' s/^.*ipaddr= (. *)/\1/p '/etc/sysconfig/network-scripts/ifcfg-eth*
Advantages:
Shorter command, easier memory
Disadvantages:
Generic not strong, get the network card configuration file IP address matching rules need to be adjusted large
Linux Text the Three Musketeers of awk
Get the IP address in the ifconfig output
Ifconfig | awk '/inet/{print} '
Get the IP address in the network card configuration file
Awk-f= '/ipaddr/{print $ '/etc/sysconfig/network-scripts/ifcfg-eth*
Advantages:
The shortest command, the most easy to remember
Disadvantages:
More general, the matching rules need to be adjusted to obtain the IP address in the NIC configuration file.
Get IP address use effect in ifconfig output
650) this.width=650; "src=" Https://s2.51cto.com/wyfs02/M02/03/E3/wKiom1mir4iRa0J5AAEzJ16rs68887.png "title=" The Three Musketeers take Ip.png "alt=" Wkiom1mir4ira0j5aaezj16rs68887.png "/>
Get the IP address usage effect in the NIC configuration file
650) this.width=650; "src=" Https://s4.51cto.com/wyfs02/M02/03/E3/wKiom1mit4rgPIVjAAB_WAcCPLY518.png "title=" Network adapter profile IP address gets the. png "alt=" Wkiom1mit4rgpivjaab_waccply518.png "/>
compared with the actual case, it is not difficult to find that the Three Musketeers of the Linux text, awk practicality and convenience are very strong (a small number of commands can handle complex text matching), so recommend the OPS engineer in the work more use awk, of course, please do not doubt, I'm not the official awk marketing staff. ^..)
This article is from the "Love Firewall" blog, be sure to keep this source http://183530300.blog.51cto.com/894387/1959780
Linux text musketeers matching NIC IP address big PK (CentOS 7 system)