I tried to create a bogon as-path list within vyos and stumbled over the problem that you cannot use the backspace character within a regex expression.
Steps to reproduce:
- install a fresh VyOS 1.5-rolling (2025-11-11)
- add the following config and commit:
set policy as-path-list bogon rule 10 regex '\s' set policy as-path-list bogon rule 10 action permit
The following error appears:
[ policy ] [3962|mgmtd] sending configuration [3963|zebra] sending configuration [3964|ripd] sending configuration [3965|ripngd] sending configuration [3966|ospfd] sending configuration [3967|ospf6d] sending configuration [3968|ldpd] sending configuration [3969|bgpd] sending configuration [3970|isisd] sending configuration [3964|ripd] done [3972|nhrpd] sending configuration [3965|ripngd] done [3962|mgmtd] done [3974|babeld] sending configuration [3966|ospfd] done Invalid character in as-path access-list \s line 3: Failure to communicate[13] to bgpd, line: bgp as-path access- list bogon seq 10 permit \s [3976|fabricd] sending configuration [3977|watchfrr] sending configuration [3969|bgpd] Configuration file[/etc/frr/frr.conf] processing failure: 13 [3963|zebra] done [3972|nhrpd] done [3968|ldpd] done [3970|isisd] done [3967|ospf6d] done [3979|staticd] sending configuration [3980|bfdd] sending configuration [3977|watchfrr] done Waiting for children to finish applying config... [3983|pim6d] sending configuration [3976|fabricd] done [3980|bfdd] done [3979|staticd] done [3974|babeld] done [3983|pim6d] done [3987|mgmtd] sending configuration [3988|zebra] sending configuration [3989|ripd] sending configuration [3990|ripngd] sending configuration [3991|ospfd] sending configuration [3992|ospf6d] sending configuration [3993|ldpd] sending configuration [3994|bgpd] sending configuration [3987|mgmtd] done [3995|isisd] sending configuration [3989|ripd] done [3993|ldpd] done [3997|nhrpd] sending configuration [3990|ripngd] done [3999|babeld] sending configuration [3988|zebra] done [4001|fabricd] sending configuration [3991|ospfd] done [3992|ospf6d] done [4002|watchfrr] sending configuration [3995|isisd] done Invalid character in as-path access-list \s line 3: Failure to communicate[13] to bgpd, line: bgp as- path access-list bogon seq 10 permit \s Invalid character in as-path access-list \s line 11: Failure to communicate[13] to bgpd, line: bgp as-path access-list bogon seq 10 permit \s [3997|nhrpd] done [4004|staticd] sending configuration [4005|bfdd] sending configuration [3999|babeld] done [3994|bgpd] Configuration file[/etc/frr/frr.conf] processing failure: 13 Waiting for children to finish applying config... [4008|pim6d] sending configuration [4001|fabricd] done [4002|watchfrr] done [4005|bfdd] done [4004|staticd] done [4008|pim6d] done [[policy]] failed Commit failed
To me it looks like the single quotation characters (') gets converted to double quotation marks (") and maybe the backslash gets interpreted then?
Tested on different rolling release version including the latest one.
The problem here is that with regex it's essential to have the backslash usable.