April 2014 - Bird-users - Mailing Lists

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

7 8

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

2 3

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.

4 13

BIRD 1.4.2 - some strange things
by Javor Kliachev 25 Apr '14

25 Apr '14

Hello, After upgrade from 1.3.9 to 1.4.2, we're observing following things: *1) Testing ADD-PATH feature on iBGP:** * With AS-PATH functionality everything looks fine but: How we may see all exported routes to given iBGP member with "add paths on" enabled. I have tried with: root@rs2-nix-bird:~# birdc show route export R0_100 count *2796* of 3377 routes for 3377 networks But obvious there is something wrong because on other side on RS1 I see the following: root@rs1-nix-bird:~# birdc show route protocol R0_200 count *3334* of 7034 routes for 6017 networks There are difference of 538 prefixes ( that are more that one path per destination ). *So my question is*: Is there any other command to see all exported prefixes when as-path is enabled. *2) BGP Route limit - strange thing:* With the new version, today I observed that when "BGP protocol" has configured limit to 1, every time when we run "birdc configure" the session from UP goes DOWN and back to UP and then stay ESTABLISHED with following reason: It is happen absolutely everytime when we run "birdc configure". Apr 23 16:17:24 rs2-nix bird: Reconfiguring Apr 23 16:17:24 rs2-nix bird: Protocol R0_187 hits route import limit (1), action: restart Apr 23 16:17:24 rs2-nix bird: R0_252: Reconfigured Apr 23 16:17:24 rs2-nix bird: Reconfigured Apr 23 16:17:26 rs2-nix bird: R0_187: Shutdown requested From *R0_187* normally we should receive only 1 prefix. When we increase the limit to 2 everything looks fine. With the old version 1.3.9 it works without restart the session. *Here is my config:* protocol bgp R0_187 from iBGP { neighbor 10.0.0.187 as 65535; import all export all table T65535; route limit 1; direct; } Thanks in advance! Best~ -- --- Find out about our new Cloud service - Cloudware.bg <http://cloudware.bg/?utm_source=email&utm_medium=signature&utm_content=link…> Access anywhere. Manage it yourself. Pay as you go. ------------------------------------------------------------------------ *Javor Kliachev* IP Engineer Neterra Ltd. Telephone: +359 2 975 16 16 Fax: +359 2 975 34 36 www.neterra.net <http://www.neterra.net>

2 2

[PATCH] More multipath support for OSPF
by Peter Christensen 23 Apr '14

23 Apr '14

Hi, I noticed that the multipath support in OSPF seems to be fairly limited. Essentially I was only able to make it do multipath if I had two interfaces connecting to the same router. At my company, we need true multipath between multiple routers using a single interface. (If I needed the other, I could use LACP) I am aware of the implications the default multipath implementation in Linux which operates on a per-packet basis, which is why we've patched our kernels to do it per-flow instead. Anyway, I seemed to have managed to make multipath work as expected - at least in our setup. (Patch attached) Essentially, I've hooked my multipath code into ri_install_ext() and ri_install_net(), where I add the equal routes if the routes share the same type, metrics and OSPF area. I realize that my add_nexthops() is /very/ similar to merge_nexthops() in functionality, but it seemed that the top_hash_entry() could be null, so I wrote a new method which did not rely on that - at the cost of more calls to copy_nexthop(), I guess. Any thoughts? Best regard Peter Christensen

2 5

question : broadcast kernel table via OSPF
by bino＠indoakses-online.com 22 Apr '14

22 Apr '14

Dear all I'm trying to learn BIRD4 to do ospf over batman-adv got to router : 1. router A 1.a. OSPF is at interface 'bat0' 1.b. Have 172.16.1.1/24 address at another interface, and have 'external route' 1.c. bird4.conf is at : http://pastebin.com/kin9MEnw 1.d. have birdc4 installed 2. router B 1.a. OSPF is at interface 'bat0' 1.b. bird4.conf is at : http://pastebin.com/XGTuHqfr 1.c. Not enough space to have birdc4 onboard Check from A. Router A using birdc4 : --------- bird> show ospf neighbors ospf1: Router ID Pri State DTime Interface Router IP 10.0.0.2 1 full/dr 00:56 bat0 10.0.0.2 bird> show ospf state area 0.0.0.0 router 10.0.0.1 distance 0 network 10.0.0.0/24 metric 1000 external 172.16.3.0/24 metric 1000 via 10.0.0.3 router 10.0.0.2 distance 1000 network 10.0.0.0/24 metric 1000 network 10.0.0.0/24 dr 10.0.0.2 distance 1000 router 10.0.0.2 router 10.0.0.1 --------- Looks like anything work fine. B. Router B, using terminal console : -------------------- root@OpenWrt:~# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 192.168.10.1 0.0.0.0 UG 0 0 0 br-lan 10.0.0.0 * 255.255.255.0 U 0 0 0 bat0 172.16.3.0 10.0.0.3 255.255.255.0 UG 0 0 0 bat0 192.168.10.0 * 255.255.255.0 U 0 0 0 br-lan ------------- Looks like : B.1. External route defined at Router-A is broadcasted ... nice B.2. Kernel route table of Router-A is NOT broadcasted. My question is : Why Kernel route table of Router-A is NOT broadcasted ? Kindly please give me any of your enlightenment to fix this problem. Sincerely -bino-

2 6

Importing routes with "strange next-hop" from the kernel
by Baptiste Jonglez 21 Apr '14

21 Apr '14

Hi, To save some IP space, we are playing a lot with /32 routes, which sometimes leads to unusual network setups. Specifically, we've hit this issue with Bird: http://marc.info/?l=bird-users&m=133465758907527&w=2 Basically, bird refuses to import a route from the kernel if the next-hop is not in a directly connected network. For instance, with a routing table like this: XX.XX.XX.32 dev eth1.101 proto static scope link src XX.XX.XX.1 XX.XX.XX.64/28 via 91.216.110.32 dev eth1.101 proto static bird will import the first route, but not the second one, spamming logs with "KRT: Received route XX.XX.XX.64/28 with strange next-hop XX.XX.XX.32". This is probably a good idea in most cases, but there are setups where these kind of routes make sense. The workaround described in the above thread ("ip addr add XX.XX.XX.1 peer XX.XX.XX.32") does not always apply, since we may want to have multiple /32 peers directly reachable on a given interface. We found another workaround (note the "onlink" flag and the "via" part): ip route add XX.XX.XX.32/32 via XX.XX.XX.32 dev eth1.101 onlink proto static This basically tells the kernel that the route we added is indeed in a connected network, so that Bird is happy. Note that subsequent routes using this /32 as next-hop also need the "onlink" flag: ip route add XX.XX.XX.64/28 via XX.XX.XX.32 dev eth1.101 proto static onlink In the hope that it will help someone someday, Baptiste

1 0

Version 1.4.3
by Ondrej Filip 15 Apr '14

15 Apr '14

Hi! We found a bug in IPv6 BGP implementation. So we decided to release 1.4.3. Ondrej

3 4

BFD on 1.4.2
by Kristoffer Egefelt 14 Apr '14

14 Apr '14

Hi, I’m trying BFD with some Force10 S4810 routers, problem is that sessions only come up every 3 or 4 times I restart bird. Also if Force10 routers are restarted, some times the sessions do not come back up. Also I have to restart bird to get it to work - birdc configure does not do it. I tried with the sysctl -w net.ipv4.ip_local_port_range="49152 65535” but this does not help either. I’m not able to get more debug info from the force10 devices than this: working : Apr 14 14:50:07: %STKUNIT0-M:CP %OSPF-5-ADJCHG: Neighbour state changed.OSPF Process 1, Nbr 77.66.22.228 on interface Vl 3000 change state from LOADING to FULL 3d0h48m : OSPFINFO: Quick Enabling BFD for NBRIP 77.66.22.228 RTRID 77.66.22.228 3d0h48m : OSPFINFO: OSPF Enabling BFD for NBRIP 77.66.22.228 Interface Vl 3000 IfIndex 1107528632 3d0h48m : OSPFINFO: Bfd Parameters interval 0 min_rx 0 Mult 0 role 0 3d0h48m : OSPFINFO: Completed Enabling BFD for NBRIP 77.66.22.228 Apr 14 14:50:08: %STKUNIT0-M:CP %BFDMGR-1-BFD_STATE_CHANGE: Changed session state to Up for neighbor 77.66.22.228 on interface Vl 3000 (diag: NO_DIAG) 3d0h48m : OSPFINFO: Ospf got BFD msg 3d0h48m : OSPFINFO: Bfd Msg Type Up for interface Vl 3000 3d0h48m : OSPFINFO: BFD Msg Up for NBRIP 77.66.22.228 RTRID 77.66.22.228, nbr bfd state Init not working : Apr 14 14:49:46: %STKUNIT0-M:CP %OSPF-5-ADJCHG: Neighbour state changed.OSPF Process 1, Nbr 77.66.22.228 on interface Vl 3000 change state from LOADING to FULL 3d0h47m : OSPFINFO: Quick Enabling BFD for NBRIP 77.66.22.228 RTRID 77.66.22.228 3d0h47m : OSPFINFO: OSPF Enabling BFD for NBRIP 77.66.22.228 Interface Vl 3000 IfIndex 1107528632 3d0h47m : OSPFINFO: Bfd Parameters interval 0 min_rx 0 Mult 0 role 0 3d0h47m : OSPFINFO: Completed Enabling BFD for NBRIP 77.66.22.228 Any hints are greatly appreciated. Thanks Regards Kristoffer

2 2

received-routes command
by Jimmy Halim 14 Apr '14

14 Apr '14

Hi guys, I am sorry if I am bringing this question again since I have been away from BIRD community for awhile. Can we show BGP “received-routes” command in BIRD right now? I understand the latest release is v1.4.2. Back in 2012, one suggestion to do it is to build up a table that receives all BGP routes and then do the filtering under pipe as per following which I haven’t tried. I hope we do not need to do this now. <snip> table t; protocol bgp { table t; import all; export all; ... } protocol pipe { peer table t; import < here goes filters for BGP export < here goes filters for BGP } <snip> Thanks, Jimmy

2 3