- Bird-users - Mailing Lists

BIRD 2.0.3 and 1.6.5
by Ondrej Filip 07 Jan '19

07 Jan '19

Dear BIRD users, we just released two new versions - 1.6.5 and 2.0.3. Many thanks mainly to Santiago and Maria! Version 1.6.5 o MRT table dumps (RFC 6396) o BGP Long-lived graceful restart o Filter: Make ifname attribute modifiable o Improved keeping track of IPv6 link-local addresses o Many bugfixes Version 2.0.3 (2019-01-05) o MRT table dumps (RFC 6396) o BGP Long-lived graceful restart o BGP: Optional import table (Adj-RIB-In) o BGP: Extend 'next hop keep' and 'next hop self' options o BGP: Improved VRF support o OSPF: Authentication trailer for OSPFv3 (RFC 7166) o Babel: New option to randomize router ID o Filter: Custom route attributes o Filter: Support for src accessor to SADR source prefix o Filter: Support for VPN_RD sets o Filter: Make ifname attribute modifiable o Perf: Protocol to measure BIRD performance internally o More verbose error messages in config processing o Log file size limit / log rotation o Many bugfixes Notes: Export of routes to RS EBGP (route server) sessions from other sources than RS EBGP sessions was changed that ASN is no longer prepended to BGP_PATH in that case. The change does not affect regular BGP configurations or regular route servers that have only RS EBGP peers. For BGP route servers and route reflectors, the default value of option 'next hop keep' was changed to a more appropriate value. Attributes for OSPF and Babel metrics are no longer reset when exported to these protocols and could be set anywhere in BIRD. As a result, OSPF metric is kept when a route is reannounced between OSPF instances. Also, when route is exported to OSPF with both ospf_metric1 and ospf_metric2 attributes it is now propagated as OSPF-E2 route instead of as OSPF-E1 route. Compiling BIRD with --enable-debug no longer automatically activates debug mode (-d option) nor local mode (-l option). Also, debug mode with output to file (-D option) no longer not forces foreground mode (-f option). The configure script now uses standard option --runstatedir, the old option --with-runtimedir is deprecated. Happy hacking in 2019! Ondrej

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Check bgp_path.len without some AS
by Xavier Trilla 06 Jan '19

06 Jan '19

Hi, For some route selection configurations I need to check the bgp_path.len without some AS numbers. I tried something like: bgp_path.delete(AS_1); bgp_path.delete(AS_2); if bgp_path.len < N then ... But doing this I modify permanently the AS path. I've tried using a temp variable, but looks like bird doesn't allow to create bgppath "variables". Any ideas about how this could be achieved? Thanks! Xavier

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cannot export routes (AS_PATH problem ?)
by Julien Sansonnens 06 Jan '19

06 Jan '19

Hi, Using BIRD 1.6.4 I want to do something very basic: export routes to a peer to allow transit. for that, I start by adding communities to my received routes, so I can distinguish the upstream. import filter { if !is_martian() && !is_self_net() && from = bgp_next_hop then { bgp_large_community.add((myas, 100, XX)); #XX for each upstream accept; } else reject; }; A community is (apparently?) added to each route. I get about 61'000 ipv6 routes from my upstream. Now I want to export them to "peer1". Here is my export function: function bgp_export_peer (){ if (myas,100,20) ~ bgp_large_community then return true; } here is the problem: it looks like only 123 routes are exported ! bird> show route export peer count 123 of 362489 routes for 61724 networks Here is an example of an exported route: 2001:9d8:200b::/48 via 2a06:1287:3308:c0c0::1 on peer-mmnetworks [mmnet 22:24:20] * (100) [AS25577i] Type: BGP unicast univ BGP.origin: IGP BGP.as_path: 207149 206499 204893 206313 6724 8560 25577 BGP.next_hop: 2a0c:b640:fffe:10:192:220:4:2 BGP.local_pref: 100 BGP.community: (666,666) (997,6499) (6724,900) (6724,960) (8560,4) (8560,10000) (57555,0) (57555,4100) (57555,4101) (65010,10000) BGP.large_community: (206313, 206313, 206313) (207149, 100, 20) and an example of a non-exported route: 2406:3003:2032::/48 via 2a06:1287:3308:c0c0::1 on peer-mmnetworks [mmnet 20:48:51] (100) [AS55430i] Type: BGP unicast univ BGP.origin: IGP BGP.as_path: 206499 6939 38861 55430 BGP.next_hop: 2a06:1287:3308:c0c0::1 fe80::b9d7:d605 BGP.med: 0 BGP.local_pref: 100 BGP.community: (0,2906) (0,6939) (0,12876) (0,12989) (0,13335) (0,15133) (0,15169) (0,16265) (0,16276) (0,16509) (0,20940) (0,22822) (0,32934) BGP.large_community: (207149, 100, 20) as you see, my lare community are added on both routes. The exported route has my AS as the first value on the left (AS_PATH), which is not the case for the non-exported route. Logically, all exported routes should have my AS on the left. Am I missing something? It's probably logical, but I do not understand what's going on here. In the same way, I can not export any route that comes from my peers (direct connection), since they have only their AS in the path. help would be highly appreciated. cheers, Julien Sansonnens

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Setting different facility parameter for logging
by Jakub Nowacki 06 Jan '19

06 Jan '19

Hi, I'm running BIRD on Arista switch that allows entering bash. What I want to achieve is to have logs from BIRD being integrated into Switch OS. Meaning when BIRD logs a message it will appear in the output of 'show logging' >From switch documentation I know it is possible, but it needs to set a certain "facility" parameter when running C function "openlog" >From BIRD source code for sysdep/unix/log.c: > if (new_syslog_name) > { > current_syslog_name = xstrdup(new_syslog_name); > > *openlog(current_syslog_name, LOG_CONS | LOG_NDELAY, LOG_DAEMON);* } What I need is instead of having LOG_DAEMON I need LOG_LOCAL4 Is it possible to set this via BIRD configuration or only way is to compile from source to achieve this? Perhaps there is another way to achieve that logging behavior? Kind regards -- Kuba

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Trouble with IPv6 and VRFs: Cannot assign requested address
by Ralf Jung 01 Jan '19

01 Jan '19

Hi all, I am playing around with VRFs in our network, and I am having trouble getting bird6 to establish its BGP sessions inside a VRF. Strangely, bird for IPv4 works with pretty much the same configuration. I have attached the full configuration. The (I think) interesting bits are > template bgp ffrl_uplink { > table ffrl; > vrf "vrf_freifunk"; > local as 64899; > import keep filtered; > import filter ebgp_ffrl_import_filter; > export filter ebgp_ffrl_export_filter; > next hop self; > direct; > }; > > protocol bgp ffrl_b_ak from ffrl_uplink { > source address 2a03:2260:0:195::2; > neighbor 2a03:2260:0:195::1 as 201701; > }; In the logs, all I get (with `debug all;` added) is > Dez 28 13:05:25 gw1.saar.freifunk.net bird6[24900]: ffrl_b_ak: Connecting to 2a03:2260:0:195::1 from local address 2a03:2260:0:195::2 > Dez 28 13:05:25 gw1.saar.freifunk.net bird6[24900]: ffrl_b_ak: Socket error: bind: Cannot assign requested address > Dez 28 13:05:25 gw1.saar.freifunk.net bird6[24900]: ffrl_b_ak: Connection closed > Dez 28 13:05:26 gw1.saar.freifunk.net bird6[24900]: ffrl_b_ak: Connect delayed by 5 seconds I tried adding `interface "tun-up-ffrl_b_ak";` (that's the interface which has the address 2a03:2260:0:194::2), to no avail. I also tried adding `interface "vrf_freifunk";`, which made the error messages go away but still no peer is listed in `birdc6 show route table ffrl`. My IPv4 configuration is almost the same, and yet there finding peers works. (Actually routing traffic doesn't work yet, but that may also be a problem with our NAT setup.) Note that I have very little experience with BGP, we use it only in an internal instance for peering with our uplink. >From some googling I found <https://bird.network.cz/pipermail/bird-users/2017-August/011440.html> which recommends adding `direct;`, but I already have that set. This is using bird 1.6.4, Linux 4.18, Debian stable. Any help would be greatly appreciated. Kind regards, Ralf

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Linux 4.20 / incomplete ipv4 addr list / RTM_GETADDR
by Arthur Gautier 31 Dec '18

31 Dec '18

Hello bird users, Today I tried to upgrade one of platform to from linux 4.19 to linux 4.20. I started noticing the bgp protocol could not start after this message: <TRACE> uplink: Waiting for 1.2.3.4 to become my neighbor The neighbor (directly connected on an interface) would never appear to bird (as in show interfaces) because the AF_INET/RTM_GETADDR reply from the kernel looks incomplete. It works fine in v6. The results from kernel are capped to 104 ip address (and we run servers with >700 ip address) on loopback. I confirm this behavour with nlmon / tcpdump / wireshark. Tested with bird v2.0.2 and v1.6.3 (debian stable). I haven't reproduced the behavior elsewhere than bird, but I believe this could prove useful to someone else. -- \o/ Arthur G Gandi.net

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Sync with userspace instead of kernel
by Cody Doucette 29 Dec '18

29 Dec '18

Is there any way in BIRD to sync the routing table directly with userspace instead of the OS kernel? We are managing forwarding tables in a userspace (DPDK) application instead of the kernel and want to avoid duplicating the table in both. I see a possible way of doing this with a patch to set `nl_pid` in nl_send() inside of sysdep/linux/netlink.c. But has anyone used BIRD for this use case before?

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[PATCH] Netlink: fix segfault on debug
by baloo＠gandi.net 28 Dec '18

28 Dec '18

From: Arthur Gautier <baloo(a)gandi.net> When enabling debug on netlink, the message formating will segfault in net_format(). From my understanding %N expects a pointer --- sysdep/linux/netlink.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/sysdep/linux/netlink.c b/sysdep/linux/netlink.c index 84591eb2ec488..36dc6f4e7b5f8 100644 --- a/sysdep/linux/netlink.c +++ b/sysdep/linux/netlink.c @@ -953,7 +953,7 @@ nl_parse_addr4(struct ifaddrmsg *i, int scan, int new) DBG("KIF: IF%d(%s): %s IPA %I, flg %x, net %N, brd %I, opp %I\n", ifi->index, ifi->name, new ? "added" : "removed", - ifa.ip, ifa.flags, ifa.prefix, ifa.brd, ifa.opposite); + ifa.ip, ifa.flags, &ifa.prefix, ifa.brd, ifa.opposite); if (new) ifa_update(&ifa); @@ -1045,7 +1045,7 @@ nl_parse_addr6(struct ifaddrmsg *i, int scan, int new) DBG("KIF: IF%d(%s): %s IPA %I, flg %x, net %N, brd %I, opp %I\n", ifi->index, ifi->name, new ? "added" : "removed", - ifa.ip, ifa.flags, ifa.prefix, ifa.brd, ifa.opposite); + ifa.ip, ifa.flags, &ifa.prefix, ifa.brd, ifa.opposite); if (new) ifa_update(&ifa); @@ -1525,7 +1525,7 @@ nl_parse_route(struct nl_parse_state *s, struct nlmsghdr *h) /* Do we know this table? */ p = HASH_FIND(nl_table_map, RTH, i->rtm_family, table_id); if (!p) - SKIP("unknown table %d\n", table); + SKIP("unknown table %d\n", table_id); if (a[RTA_SRC] && (p->p.net_type != NET_IP6_SADR)) SKIP("src prefix for non-SADR channel\n"); -- 2.20.1

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ospf module code structure
by Alon Dotan 18 Dec '18

18 Dec '18

Hey All, can I get some reference to the section ion the code that OSPF make the routing decisions (add, merge, delete routs)? Thanks,

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BGP developer question for implementing future feature
by Mattia Milani 17 Dec '18

17 Dec '18

Hello, I'm implementing a strange feature for a research. Protocol: BGP Bird version: 2.0.1 I would like to send an UPDATE message after received one that didn't update the RT (with some other constraints to avoid continuous UPDATE sending), but I'm stocked. I would like to do it at the end of the function: bgp_rx_update(struct bgp_conn *conn, byte *pkt, uint len) The UPDATE that I have to trigger use the same connection from the one I have received and the same network information, but I don't know how to trigger it. Do you have any suggestion? thanks, Mattia

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