Maximum route metric on Linux
Ever wondered what is the maximum route metric value you can configure on Linux? man interface
and man ip
state that route metric is a number, but don’t specify its range.
# ip route add 192.168.113.0/24 via 10.0.10.1 metric 0 # ip route add 192.168.113.0/24 via 10.0.10.1 metric 4294967295 # ip route add 192.168.113.0/24 via 10.0.10.1 metric 4294967296 Error: argument "4294967296" is wrong: "metric" value is invalid # ip route 192.168.113.0/24 via 10.0.10.1 dev eth0 192.168.113.0/24 via 10.0.10.1 dev eth0 metric 4294967295
It looks like Linux route metric is an unsigned 32-bit integer, ranging from 0 to 4294967295. As you already know a route with the lowest metric is preferred.