Changing default or static route gateway on 2.5.0 does not remove old route
2.5.0 has multi-path (RADIX_MPATH) enabled in its kernel (#9544) which allows multiple routes to the same destination to exist in the routing table.
This leads to a problem when changing the default gateway on system_gateways.php. When the user selects a different default gateway, then saves and applies changes, the old default is not removed:
WAN gateway selected as default:
: netstat -rn4 | grep default default 198.51.100.1 UGS em0
Default changed to WAN2 gateway, then save/apply:
: netstat -rn4 | grep default default 198.51.100.1 UGS em0 default 203.0.113.1 UGS em2
The second route must be removed by hand (e.g.
route delete default 198.51.100.1), or a reboot would also clear it.