bgpq3 man page

bgpq3 — bgp filtering automation for cisco and juniper routers

Synopsis

bgpq3 [-h host] [-S sources] [-EP] [-f asn | -G asn] [-346AbDdJjX] [-r len] [-R len] [-m max] [-W len] OBJECTS [...]

Description

The bgpq3 utility used to generate Cisco and Juniper prefix-lists, extended access-lists, policy-statement terms and as-path lists based on RADB data.

The options are as follows:

-3

assume that your device is asn32-safe.

-4

generate IPv4 prefix/access-lists (default).

-6

generate IPv6 prefix/access-lists (IPv4 by default).

-A

try to aggregate prefix-lists as much as possible (not all output formats supported).

-b

generate output in BIRD format (default: Cisco).

-d

enable some debugging output.

-D

use asdot notation for Cisco as-path access-lists.

-E

generate extended access-list (Cisco) or policy-statement term using route-filters (Juniper).

-f number

generate input as-path access-list.

-G number

generate output as-path access-list.

-h host

host running IRRD database (default: whois.radb.net).

-J

generate config for Juniper (default: Cisco).

-j

generate output in JSON format (default: Cisco).

-m len

maximum prefix-length of accepted prefixes (default: 32 for IPv4 and 128 for IPv6).

-M match

extra match conditions for Juniper route-filters.

-l name

name of generated entry.

-P

generate prefix-list (default, backward compatibility).

-r len

allow more specific routes starting with specified masklen too.

-R len

allow more specific routes up to specified masklen too.

-S sources

use specified sources only (default: RADB,RIPE,APNIC).

-T

disable pipelining.

-W len

generate as-path strings of no more than len items (use 0 for inifinity).

-X

generate config for Cisco IOS XR devices (plain IOS by default).

OBJECTS

means networks (in prefix format), autonomous systems, as-sets and route-sets.

Examples

Generating named juniper prefix-filter for AS20597: ~>bgpq3 -Jl eltel AS20597 policy-options { replace:
prefix-list eltel {
81.9.0.0/20;
81.9.32.0/20;
81.9.96.0/20;
81.222.128.0/20;
81.222.192.0/18;
85.249.8.0/21;
85.249.224.0/19;
89.112.0.0/19;
89.112.4.0/22;
89.112.32.0/19;
89.112.64.0/19;
217.170.64.0/20;
217.170.80.0/20;
} }

For Cisco we can use aggregation (-A) flag to make this prefix-filter more compact: ~>bgpq3 -Al eltel AS20597 no ip prefix-list eltel ip prefix-list eltel permit 81.9.0.0/20 ip prefix-list eltel permit 81.9.32.0/20 ip prefix-list eltel permit 81.9.96.0/20 ip prefix-list eltel permit 81.222.128.0/20 ip prefix-list eltel permit 81.222.192.0/18 ip prefix-list eltel permit 85.249.8.0/21 ip prefix-list eltel permit 85.249.224.0/19 ip prefix-list eltel permit 89.112.0.0/18 ge 19 le 19 ip prefix-list eltel permit 89.112.4.0/22 ip prefix-list eltel permit 89.112.64.0/19 ip prefix-list eltel permit 217.170.64.0/19 ge 20 le 20 - you see, prefixes 89.112.0.0/19 and 89.112.32.0/19 now aggregated into single entry 89.112.0.0/18 ge 19 le 19.

Well, for Juniper we can generate even more interesting policy-options, using -M <extra match conditions>, -R <len> and hierarchical names: policy-options {
policy-statement eltel {
term specifics { replace:
from {
community blackhole;
route-filter 81.9.0.0/20 prefix-length-range /29-/32;
route-filter 81.9.32.0/20 prefix-length-range /29-/32;
route-filter 81.9.96.0/20 prefix-length-range /29-/32;
route-filter 81.222.128.0/20 prefix-length-range /29-/32;
route-filter 81.222.192.0/18 prefix-length-range /29-/32;
route-filter 85.249.8.0/21 prefix-length-range /29-/32;
route-filter 85.249.224.0/19 prefix-length-range /29-/32;
route-filter 89.112.0.0/17 prefix-length-range /29-/32;
route-filter 217.170.64.0/19 prefix-length-range /29-/32;
}
}
} } generated policy-option term now allows all specifics with prefix-length between /29 and /32 for eltel networks if they match with special community

Of course, this version supports IPv6 (-6): ~>bgpq3 -6l as-retn-6 AS-RETN6 no ipv6 prefix-list as-retn-6 ipv6 prefix-list as-retn-6 permit 2001:7fb:fe00::/48 ipv6 prefix-list as-retn-6 permit 2001:7fb:fe01::/48 [....] and support for ASN 32 is also here ~>bgpq3 -J3f 112 AS-SPACENET policy-options { replace:
as-path-group NN {
as-path a0 "^112(112)*$";
as-path a1 "^112(.)*(1898|5539|8495|8763|8878|12136|12931|15909)$";
as-path a2 "^112(.)*(21358|23456|23600|24151|25152|31529|34127|34906)$";
as-path a3 "^112(.)*(35052|41720|43628|44450|196611)$";
} } see AS196611 in the end of the list ? That's AS3.3 in 'asplain' notation.

For non-ASN32 capable routers you should not use switch -3, and the result will be next: ~>bgpq3 -f 112 AS-SPACENET no ip as-path access-list NN ip as-path access-list NN permit ^112(_112)*$ ip as-path access-list NN permit ^112(_[0-9]+)*_(1898|5539|8495|8763)$ ip as-path access-list NN permit ^112(_[0-9]+)*_(8878|12136|12931|15909)$ ip as-path access-list NN permit ^112(_[0-9]+)*_(21358|23456|23600|24151)$ ip as-path access-list NN permit ^112(_[0-9]+)*_(25152|31529|34127|34906)$ ip as-path access-list NN permit ^112(_[0-9]+)*_(35052|41720|43628|44450)$

AS196611 is no more in the list, however, AS23456 (transition AS) would be added to list if it were not present.

Diagnostics

When everything is OK, bgpq3 generates access-list to standard output and exits with status == 0. In case of errors they are printed to stderr and program exits with non-zero status.

See Also

http://www.radb.net/ Routing Arbiter project http://tools.ietf.org/html/draft-michaelson-4byte-as-representation-05 for information on 'asdot' and 'asplain' notations. http://www.cisco.com/en/US/docs/ios/12_0s/release/ntes/120SNEWF.html#wp3521658 for information on Cisco implementation of ASN32.

Author

Alexandre Snarskii ⟨snar@snar.spb.ru⟩

Info

October 27, 2008