How does one get ip addr show to only show links of a specific type, without using a secondary process like grep to do filtering?
According to man 8 ip-address, this should be possible using the following, but when I run these, I get no results:
ip addr show type "link/loopback"
ip addr show type "loopback"
The short and simple:
hostname -i
Usually, I'm not looking for loopback but the ip so
hostname -I
And if you want both while reducing the textual noise and adding color
ip addr | grep inet
I wound up doing this in Python. I haven't tried translating this using grep.
import re
import shlex
import subprocess
""" Return a list of interface name strings """
RE_PATT = "^\d+: (\w+).+\n +link/loopback"
proc = subprocess.run(
shlex.split("ip link show"),
stdout=subprocess.PIPE,
universal_newlines=True,
)
interface_list = re.findall(RE_PATT, proc.stdout, re.MULTILINE)
TYPE := [ bridge | bridge_slave | bond | bond_slave | can | dummy | hsr | ifb | ipoib | macvlan | macvtap | vcan | veth | vlan | vxlan | ip6tnl | ipip | sit | gre | gretap | erspan | ip6gre | ip6gretap | ip6erspan | vti | vrf | nlmon | ipvlan | lowpan | geneve | macsec ]loopbackorether. That's disappointing.loand filter on IFNAME instead, soip addr show lowill work. Not sure if it is relevant for your use though.link/ether,link/loopback, etc. lines, instead of filtering an interface.