====== Exclude Virtual Interfaces in IP Command ======
Apr 2023
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In Kubernetes deployments, there are always a number of virtual interfaces, this isn't an issue until you are trying to look at the details of physical interfaces, and the virtual ones scroll the physical ones off the page. You can use a grep command to hide the virtual interfaces to stop this this though.
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Lets say I use an IP command to list the interfaces on a Linux instance.
ip -br -c a
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I will see something similar to the following output.
lo UNKNOWN 127.0.0.1/8 ::1/128
eth2 UP 11.0.200.2/16 fe80::76fe:48ff:fe45:e65e/64
eth3 DOWN
eth4 UP 12.0.200.4/16 fe80::76fe:48ff:fe45:e660/64
eth5 DOWN
eth0 UP 10.43.30.200/24 fe80::76fe:48ff:fe45:1eee/64
eth1 DOWN
internalk3s0 UNKNOWN 192.168.255.1/24
kube-ipvs0 DOWN 10.1.0.1/32 10.1.58.55/32 10.1.139.197/32 10.1.224.155/32 10.1.15.231/32 10.1.234.150/32 10.1.224.182/32 10.1.82.169/32 10.1.88.39/32 10.1.113.246/32 10.1.0.10/32 10.1.92.105/32 10.1.242.227/32 10.1.136.136/32 10.1.147.213/32 10.1.105.61/32 10.1.14.221/32 10.1.62.150/32 192.168.255.1/32 10.1.142.50/32 10.1.227.44/32 10.1.178.20/32 10.1.37.6/32 10.1.220.215/32 10.1.46.190/32 10.1.188.12/32 10.1.27.143/32 10.1.75.75/32 10.1.45.171/32 10.1.242.58/32 10.1.146.97/32 10.1.119.162/32 10.1.133.120/32 10.1.193.167/32 10.1.44.38/32 10.1.226.76/32 10.1.60.158/32
flannel.1 UNKNOWN 10.0.0.0/32 fe80::c426:bfff:fe61:77b7/64
cni0 UP 10.0.0.1/24 fe80::98df:c5ff:fe4f:e664/64
veth5b959f30@if2 UP fe80::483d:bcff:fe00:bf49/64
veth1b36bc0e@if2 UP fe80::a479:9ff:feec:741b/64
vetheafccb8b@if2 UP fe80::fc7a:eaff:fe49:ade4/64
veth6cab92f8@if2 UP fe80::80a7:bfff:fe8f:504/64
vetha6ca6c5c@if2 UP fe80::784a:afff:fe3e:511/64
vetha47d76c5@if2 UP fe80::94e0:b3ff:fe8f:8b1b/64
veth78d7ae7b@if2 UP fe80::1083:91ff:fe56:b7ad/64
vethbfbdce9e@if2 UP fe80::d4a7:13ff:fe38:bb29/64
veth12caaf80@if2 UP fe80::104e:19ff:fe18:c5bf/64
vethecaec700@if2 UP fe80::5c86:38ff:fedb:5bfa/64
vethf759469f@if2 UP fe80::a455:1eff:fed1:d90/64
veth5b8833a6@if2 UP fe80::cad:7aff:fea3:d84a/64
veth18c2a62d@if2 UP fe80::40d1:4ff:fe6e:d485/64
veth8e69b358@if2 UP fe80::f0be:46ff:fee7:fb23/64
veth62243482@if2 UP fe80::c52:58ff:fe6e:a289/64
veth4def4cbc@if2 UP fe80::106e:beff:fe82:90d9/64
veth6583da97@if2 UP fe80::e8dd:3ff:fe64:9071/64
veth30a60131@if2 UP fe80::5097:44ff:fea9:9783/64
veth17bbb9b4@if2 UP fe80::4067:f9ff:fe92:3663/64
vetha71f5d6e@if2 UP fe80::6493:5cff:fef8:aadd/64
veth4171ad7f@if2 UP fe80::a9:96ff:fe0e:311/64
vethffca2e81@if2 UP fe80::302f:f9ff:fee5:8f50/64
vethce83eb59@if2 UP fe80::c0f8:c5ff:fe07:f5e9/64
veth30897d87@if2 UP fe80::c0ac:bff:fe78:6080/64
vethe9389c32@if2 UP fe80::d810:1ff:fe14:5285/64
vethde8e4fea@if2 UP fe80::547d:b0ff:fe0b:1f1c/64
vethc3a4bead@if2 UP fe80::9c59:dcff:fee7:6f8e/64
veth4f402974@if2 UP fe80::f490:b3ff:fe57:44e6/64
veth0cdaa299@if2 UP fe80::283b:a8ff:fe3e:a4de/64
vethb0dc4ed2@if2 UP fe80::e07f:9aff:fea0:99ea/64
veth1c3166fa@if2 UP fe80::8c40:cbff:fe20:ec8/64
veth2255cafe@if2 UP fe80::8df:44ff:feb0:4386/64
vethb12cf176@if2 UP fe80::48b8:e7ff:fe3e:c539/64
veth931f4dd1@if2 UP fe80::9cad:31ff:fe6d:b6bf/64
vetha3c59775@if2 UP fe80::70fe:feff:fe35:d5a7/64
veth2ceb7cf6@if2 UP fe80::a008:eeff:feb6:4cba/64
veth2199c7d1@if2 UP fe80::f4c1:e4ff:fefa:465c/64
Unfortunately, the vethxxxxxx interfaces will cause the physical interface details at the top of the list out of the view of the console, so what we really need is a way to filter this result. This can be done using grep and a filter to format our output.
ip -br -c a |grep -v veth
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This will hide anything containing the letters veth.
lo UNKNOWN 127.0.0.1/8 ::1/128
eth2 UP 11.0.200.2/16 fe80::76fe:48ff:fe45:e65e/64
eth3 DOWN
eth4 UP 12.0.200.4/16 fe80::76fe:48ff:fe45:e660/64
eth5 DOWN
eth0 UP 10.43.30.200/24 fe80::76fe:48ff:fe45:1eee/64
eth1 DOWN
internalk3s0 UNKNOWN 192.168.255.1/24
kube-ipvs0 DOWN 10.1.0.1/32 10.1.58.55/32 10.1.139.197/32 10.1.224.155/32 10.1.15.231/32 10.1.234.150/32 10.1.224.182/32 10.1.82.169/32 10.1.88.39/32 10.1.113.246/32 10.1.0.10/32 10.1.92.105/32 10.1.242.227/32 10.1.136.136/32 10.1.147.213/32 10.1.105.61/32 10.1.14.221/32 10.1.62.150/32 192.168.255.1/32 10.1.142.50/32 10.1.227.44/32 10.1.178.20/32 10.1.37.6/32 10.1.220.215/32 10.1.46.190/32 10.1.188.12/32 10.1.27.143/32 10.1.75.75/32 10.1.45.171/32 10.1.242.58/32 10.1.146.97/32 10.1.119.162/32 10.1.133.120/32 10.1.193.167/32 10.1.44.38/32 10.1.226.76/32 10.1.60.158/32
flannel.1 UNKNOWN 10.0.0.0/32 fe80::c426:bfff:fe61:77b7/64
cni0 UP 10.0.0.1/24 fe80::98df:c5ff:fe4f:e664/64
No our list is much more readable.
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We could refine this output with multiple exclusions using the -e switch:
ip -br -c a |grep -v -e "veth" -e "cni0" -e "flannel" -e "kube" -e "internal" -e"lo"
This give the following output.
eth2 UP 11.0.200.2/16 fe80::76fe:48ff:fe45:e65e/64
eth3 DOWN
eth4 UP 12.0.200.4/16 fe80::76fe:48ff:fe45:e660/64
eth5 DOWN
eth0 UP 10.43.30.200/24 fe80::76fe:48ff:fe45:1eee/64
eth1 DOWN
This is a lot to type/remember, but you could make a script out of it.
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