July 2014 - Bird-users - Mailing Lists

New in BIRD
by Ilias Pallikarakis 23 Aug '16

23 Aug '16

Hi, I recently started trying to learn BIRD. I should also mention I have no previous experience with any other Routing daemon either. I want to configure a bgp monitor for both ipv4 and ipv6. I am running BIRD in a Ubuntu 13.10 VM. I managed to install both bird and bird6 but I have some problems with the configurations. In ipv4 : I created a very simple configuration which I attach. The conf is compiled but in birdc the bgp session is considered idle. I tried to do a tcpdump and found that the router sends a TCP SYN on the VM's bgp port but the VM responds with a RST and never tries to set a BGP session itself. In ipv6 : No matter the configuration (my configuration or the sample coming with bird6 or examples found on the web) the configuration is not compiled giving the following error : BIRD ipv6 doesn't run (bird: /usr/local/etc/bird6.conf, line 1: Router ID must be configured manually on IPv6 routers) Could anyone give me some pointers on what I am doing wrong ? Thank you for your help, Ilias Pallikarakis

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IS-IS
by kveri new 01 Jun '15

01 Jun '15

Hello, I would like to implement IS-IS as a part of my master thesis. Are there any apparent problems which would prevent successful implementation, political and/or technical? Also I would like to hear opinions of the authors. Implementation timeframe is 2013 (if we live past 21th). Regards, Martin Čechvala Faculty of Informatics and Information Technologies Slovak Technical University

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RIP not doing "triggered update" following route deletion
by Tore Anderson 15 Oct '14

15 Oct '14

I've noticed that BIRD doesn't withdraw (i.e., advertising them with metric 16) RIP routes when they disappear from the routing table. This means that the neighbour router ends up waiting for the route to time out before ceasing to send traffic to the BIRD router, rather than doing so immediately. I'm running v1.4.0 with a bird.conf containing: log syslog { info, remote, warning, error, auth, fatal }; router id 192.0.2.1; protocol device {} protocol direct {} protocol rip { interface "*" { mode nolisten; ttl security on; }; import none; export all; } To reproduce the issue, look at "tcpdump -v port 520" while doing: 1) ip address add 192.0.2.2/32 dev lo -> a triggered update appears (advertising 192.0.2.2/32) 2) ip address delete 192.0.2.2/32 dev lo -> a triggered update doesn't appear (it should have) For what it's worth, step #2 does increase the RIP protocol's "Export withdraws" counter. This issue also applies to RIPng/bird6. AFAICT, not sending these triggered updates immediately is a standards violation. Quoting RFC 1812 F.2: «A router MUST send a triggered update when routes are deleted or their metrics are increased.» Also see RFC 2453 section 3.10.1. Tore

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Version 1.4.4
by Ondrej Filip 07 Oct '14

07 Oct '14

Dear Bird users, the new version is out: Version 1.4.4 o Extended OSPF multipath support. o Default router preference for RAdv. o Significant changes in socket layer. o Important bugfix in BGP. o Several minor bugfixes. Ondrej

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BFD implementation in 1.4.0
by Aleksey Berezin 02 Sep '14

02 Sep '14

Hi there! Firstly, sorry for my French ;) Recently I tried to test BFD implementation in 1.4.0 BIRD release. Case is "OSPF ECMP with less-second failover". On one side - Extreme Networks switches, other side - several boxes with Debian and BIRD, of course. So, I find out several annoying things. First thing: BIRD BFD implementation uses non-RFC5881 source UDP port for outgoing packets. Here some tcpdump: =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 20:34:21.355747 <BIRD_BOX_MAC> > <EXTREME_SW_MAC>, ethertype 802.1Q (0x8100), length 70: vlan <vlan>, p 0, ethertype IPv4, (tos 0xc0, ttl 255, id 20806, offset 0, flags [none], proto UDP (17), length 52) <BIRD_BOX_IP>.39156 > <EXTREME_SW_IP>.3784: BFDv1, length: 24 Control, State Init, Flags: [none], Diagnostic: No Diagnostic (0x00) Detection Timer Multiplier: 5 (5000 ms Detection time), BFD Length: 24 My Discriminator: 0x8a82eb8a, Your Discriminator: 0x00000002 Desired min Tx Interval: 1000 ms Required min Rx Interval: 10 ms Required min Echo Interval: 0 ms =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= I saw many messages in switch logs: > <Warn:BFD.RxPktInv> Received BFD an invalid packet on VLAN <vlan> Error:Invalid UDP src port Number BFD session between BIRD and Extreme Networks switch can't be established. So, src port for outgoing BFD-packet from BIRD is 39156, when RFC5881 contains: =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 4. Encapsulation BFD Control packets MUST be transmitted in UDP packets with destination port 3784, within an IPv4 or IPv6 packet. The source port MUST be in the range 49152 through 65535. =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ok, fixing (only for test purposes): =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= root@debian-1:~# sysctl net.ipv4.ip_local_port_range net.ipv4.ip_local_port_range = 32768 61000 root@debian-1:~# sysctl -w net.ipv4.ip_local_port_range="49152 65535" net.ipv4.ip_local_port_range = 49152 65535 root@debian-1:~# sysctl net.ipv4.ip_local_port_range net.ipv4.ip_local_port_range = 49152 65535 =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= After this BFD session was estabilished. Of course, net.ipv4.ip_local_port_range tuning seems to be not usable in production environment, and need to be fixed in BIRD, I think. Just because some network hardware vendors interprets RFC's exactly as written ;) But now - second thing: 'protocol bfd' block in bird.conf useless. Here part of config: =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= protocol bfd FOR_OSPF { interface <BIRD_BOX_IP>/32 { interval 50 ms; min rx interval 50 ms; # presence of this string by the docs does not matter min tx interval 50 ms; # presence of this string by the docs does not matter multiplier 3; }; neighbor <EXTREME_SW_IP> dev "<BIRD_BOX_IP>" local <BIRD_BOX_IP>; # presence of this string by the docs does not matter }; protocol ospf OSPF1 { ... area 0.0.0.0 { interface <BIRD_BOX_IP>/32 { ... bfd; }; }; ... }; =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= And what I see with tcpdump: =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 13:09:05.433336 <BIRD_BOX_MAC> > <EXTREME_SW_MAC>, ethertype 802.1Q (0x8100), length 70: vlan <vlan>, p 0, ethertype IPv4, (tos 0xc0, ttl 255, id 6662, offset 0, flags [none], proto UDP (17), length 52) <BIRD_BOX_IP>.62698 > <EXTREME_SW_IP>.3784: BFDv1, length: 24 Control, State Up, Flags: [none], Diagnostic: No Diagnostic (0x00) Detection Timer Multiplier: 5 (500 ms Detection time), BFD Length: 24 My Discriminator: 0x35e75227, Your Discriminator: 0x00000007 Desired min Tx Interval: 100 ms Required min Rx Interval: 10 ms Required min Echo Interval: 0 ms =-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= There is no any configured intervals and multiplier. Just default values. I think this is not correct. Maybe I misconfigure BIRD? Please advise. Thanks for attention.

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L2 MTU issues - is BFD proper solution?
by Bartosz Radwan 15 Aug '14

15 Aug '14

We experienced recently several times issues caused by eg. EAPS path swich in one of our L2 transmission providers (new path MTU was not big enough due to jumbo frames not enabled - that's what they told us, but in fact it does not meter - it's out of our control). From our point of view this situation sucks - we have several BGP sessions, terminated on 2 different BGP routers in different data centers, but problems as descripbed above in just one L2 provider network may cause our all services are not fully operational - especially when afeccted BGP sessions provides best routes for some popular services like FB, YT or… redtube.com ;). So, the question: is BFD able to detect broken L2 MTU and if detected - disable affected BGP sessions? If not BFD, any other ideas? It's possible to detect L2 problems outside bird and then disable protocols, but this may be complicated and error prone, so in fact - i do not want to to that. -- A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? Bartosz Radwan

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Prefix count limit?
by Tom van Leeuwen 31 Jul '14

31 Jul '14

Hi everyone, I got an announcement from my iptransit provider stating the ipv4 routing table size has now exceeded 500k routes, so I thought lets check if bird is able to handle this and actually find out if there are any limitations. I could not find it on the website, but if I remember correctly the amount of routes is only impacted by the amount of memory the bird server has? Kind regards, Tom van Leeuwen

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how to use "Operators" in bird
by 曾小小 30 Jul '14

30 Jul '14

hi, My system is Ubuntu 13.04, kernel version is 3.8.0-21-generic, bird version is 1.4.4. Device configuration is as follows: 1. about function function rt_import (int asn; int set peer_asns; prefix set peer_nets) { if (net ~ peer_nets) then return false!; } 2. about filter filter bgp_upstream { if rt_import (64609, [64609], [192.168.1.0/24]) then reject; } In the above function, I use net ~ peer_nets to filter out peer_nets route, but in filter medium, peer_nets defined as 192.168.1.0/24, which would lead to such a fine route 192.168.1.1 will be filtered out. If the test using the "-" operator, will lead filter to filter out all the routes. Why? In the above example, how can I use "operators" to achieve peer_nets defined as 192.168.1.0/24, 192.168.1.1 subnet address to ensure it will not be filtered out. Thank you very much for nothing always help, thanks.

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Protocol static with virtual devices
by kiwi 30 Jul '14

30 Jul '14

Hi everyone, many months ago I tried to install a route on a virtual device (IPIP, GRE, doesn't matter) like this: protocol static { 1.2.3.0/24 via "ipip0"; } It didn't worked out. So I've choosen another non-bird solution. Yesterday I tried it again and it still does not work. Now I've tried to investigate a bit: birdc show interfaces: ipip0 DOWN (index=39) PtP Multicast AdminUp LinkUp MTU=16412 Looks like bird don't want to install the route because of the devices state (AdminUp, LinkUp but DOWN). "Protocol device" is active (scan time 10) and birdrestarts also don't help. bird> show route for 1.2.3.0/24 Network not in table Any ideas? Best regards, Manu

2 1

Ubuntu / debian bird packaging
by Alex Bligh 25 Jul '14

25 Jul '14

Previous packaging had the init script read /etc/default/bird, which pretty standard Modern packaging seems to look for /etc/bird/envvars Is there a reason for this change (which broke stuff here) and would reading both be better? -- Alex Bligh

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