April 2012 - Bird-users - Mailing Lists

upgrade 1.2.4 - 1.3.1 reverted
by Arjan Filius 24 Oct '12

24 Oct '12

Hello, upgraded from bird 1.2.4 to bird 1.3.1 last weekend, but needed to revert due to complaints from high bgp traffic to bgpmon.net and 100% cpu load on a 2x bird bgp routers setup connected with iBGP. Did some research, and noticed a high bgp traffic situation on the iBGP sessions (about 10.000 bgp packets in 1.7 second) Based on graph statistics, i noticed a irregular traffic on the trans-ip's as well (noticed after rollback in statistical graphs) In the logging (mostly on the first bgp router) , i noticed quite some messages (33414 in ~12h) like: 29-05-2011 10:57:49 <WARN> Next hop address X.X.X.242 resolvable through recursive route for X.X.X.0/24 29-05-2011 10:57:49 <WARN> Next hop address Y.Y.35.194 resolvable through recursive route for Y.Y.32.0/19 29-05-2011 10:57:52 <WARN> Next hop address X.X.X.241 resolvable through recursive route for X.X.X.0/24 29-05-2011 10:57:52 <WARN> Next hop address X.X.X.242 resolvable through recursive route for X.X.X.0/24 29-05-2011 10:57:55 <WARN> Next hop address Y.Y.35.194 resolvable through recursive route for Y.Y.32.0/19 29-05-2011 10:57:55 <WARN> Next hop address X.X.X.241 resolvable through recursive route for X.X.X.0/24 29-05-2011 10:57:55 <WARN> Next hop address X.X.X.242 resolvable through recursive route for X.X.X.0/24 These are the subnets of the upstream trans-ip links of it's neigbor router On the second (neighbor) bgp router, noticed only such 15 recursive messages I had those upstream trans-ip interface IP's manually added once to the bird.conf with a "protocol static" definition with a subnet of /32. I thought this might be the problem, and wel, disabled those static trans-ip interface routes, except i forgot one. Noticed a lower CPU afterwards, but problem persisted, and i reverted to 1.2.4. Later i noticed i missed one static route to disable, but no time left to upgrade and test again. I think i should have looked at the recursive routes in bird, but i didn't. Does one know what was going on here, and what to do to prevent it when executing another upgrade? I created a 10.000 packet tcpdump capture (full size) of an iBGP session, in case somone would like to look at it. Regards, Arjan Filius -- Arjan Filius mailto:iafilius@xs4all.nl

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Route aggregation in BIRD - how?
by Maciej Wierzbicki 20 Aug '12

20 Aug '12

Hello. Case study: * importing full BGP table from various uplinks * some routes received by BGP are being exported via OSPF to core1, using filters: (source = RTS_BGP && bgp_path ~ [= * ASNXYZ * =]) Question: how to aggregate routes (whenever possible) before exporting them via OSPF to core? Example: lets say that I've received a.b.c.d/22 and a.b.c.d/24 from asnXYZ via BGP. Lets say that I want to export routes with asnXYZ in aspath via ospf to core1 switch. Obviously, a.b.c.d/24 is in a.b.c.d/22, so I would like to export only a.b.c.d/22. Is it doable in bird? If yes, any hint/keywords in doc? -- * Maciej Wierzbicki * At paranoia's poison door * * VOO1-RIPE *

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Re: Route aggregation in BIRD - how?
by Ondrej Zajicek 14 Aug '12

14 Aug '12

On Thu, Feb 23, 2012 at 01:13:16AM +0000, Alexander V. Chernikov wrote: > On 24.01.2012 22:12, Alexander V. Chernikov wrote: >> Ondrej Zajicek wrote: >>> On Mon, Jan 23, 2012 at 10:30:48PM +0400, Alexander V. Chernikov wrote: >>>> On 23.01.2012 22:00, Ondrej Zajicek wrote: >>>>> On Mon, Jan 23, 2012 at 08:14:28PM +0400, Alexander V. Chernikov wrote: >>>>>> On 23.01.2012 20:01, Maciej Wierzbicki wrote: >>>>>>> Hello. > > Hello. > Long story short, beta for aggregation protocol is attached. Thanks, i will look at it. -- Elen sila lumenn' omentielvo Ondrej 'SanTiago' Zajicek (email: santiago(a)crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."

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real broadcast mode
by Tapio Haapala 16 May '12

16 May '12

Hello, Bird supports with ospf type broadcast. Looks that it actually means hat you execpt from "type mcast". On several networks multicast is broken. Yes it is broken and we cannot do nothing for that because they are metro ethernet and odsl (operator dsl) networks and they are leased from local operators. One solution is make mtmp configuration but if you have 100 router it is nightmare. So I humbly asking new feature. It is real broadcast type. Because of compatibility reasons it is unpossible use type bcast for that and rename multicast for type mcast I suggest that new type is rbcast. It is extension over rfc but it is really usefull one. On real broadcast packets send to 255.255.255.255 so they does not get meshed up with multicast specific rules. I have hear many times "but multicast is broadcast on l2 networks". Pleas dont use that argument. Truck is car, pickup is car but it does not mean that truck is pickup. Some times you have roads where you can drive with pickups but not with trucks. First time when I face this problem I was thiking that "ok this is corner case and solution is ptmp". When we start get these cases on several networks with several operators and several vendors, I start thinking that maybe there is improvement need on ospf. ps How many elese had suffer problems with metro ethernet or dsl network that devices delivery unicast traffic and bcast traffic to ff:ff:ff:ff:ff:ff but does not delivery traffic to 01:00:5e:00:00:05 -- F-Solutions Oy Tapio Haapala PL 7, 90571 Oulu GSM 040-0998371 Skype burner- IRC Burner@ircnet

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Fwd: Received route with strange next-hop
by Christian Kölpin 04 May '12

04 May '12

Hello Community First I have to say, the problem occurs in a lab/soho environment, so it might be unusal to normal bird purposes. I'am running two routers who uses bird/OSPF to exchange their routing tables. One router represents the firewall and "internet-connection", the second runs several VPN daemons (IPSec, OpenVPN, L2TP). Some foreign Routers are connected via these VPNs and running OSPF as well (mix quagga/bird). All is running well except some "stange next-hop" messages. The Problem is, I don't understand why i get these messages. To me, the routes looks ok. So I don't understand the problem at all. Maybe someone can help me to understand it. OS: linux/openwrt Bird: version 1.3.3 I have two "problematic" routes who leads to "strange next-hop" messages: 1) network: 192.168.100.128 gateway 192.168.100.130 netmask 255.255.255.128 (/25) bird-message: KRT: Received route 192.168.100.128/25 with strange next-hop 192.168.100.130 add info: the network is a OpenVPN "Roadwarrior"-network. There is a tun0-ptp-interface with 192.168.100.129 as local an 192.168.100.130 as foreign address 2) network 0.0.0.0 (default) gateway 84.57.128.1 netmask 0.0.0.0 bird-message: KRT: Received route 0.0.0.0/0 with strange next-hop 84.57.128.1 add info: the default route is injected by the pppd when the router connects to my german-isp via pppoe (DSL). I have a ptp-interface with my dynamic ip an the GW-address as foreign address Both gateways are listed in the kernel-routing as directly connected via a /32 route (eg 84.57.128.1 gw 0.0.0.0 netmask 255.255.255.255) If I start the BIRD instances on both routers and the problematic routes are present in the kernel table, all works well. No Messages, the routes are "learned" trough the "kernel-protocol", handed over to the OSPF-protocol and propagated to the other routers. All is fine. But if the ISP forcing a reconnect (its a contract without static ip) or the openvpn-daemon needs to restart, the problem starts. The mentioned messages appears in syslog and no routes are learned and propagated. I get around this, whit defining some stub-networks in ospf or a static-default route. Interesting fact: even if a DON'T put activate the kernel learn-switch and set explicit import to none i get these message. I have to set the kernel scan-time to 0 to suppress continuous log-spamming with the message. protocol kernel { export all; import none; scan time 0; } So what I'm doing wrong? How can I connect bird and ptp-interfaces the right way? greetings Raptor 2101

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2 routers and 4 peers route export selection
by Laurent GUERBY 27 Apr '12

27 Apr '12

Hi, I have two debian BIRD routers R1 and R2 connected by an iBGP session, both R1 and R2 are connected to two eBGP peers each: P1 <==> R1 <===> R2 <===> P3 P2 <==> | | <===> P4 Some routes are imported by R1 from both P1 and P2 and I want to continue to export to P3 a mix of routes from P1 and P2 (which is what is done by the iBGP session and preferences) but now I want to export to P4 only the routes imported from P2 and no route imported from P1. How would you do that with BIRD? Thanks in advance, Laurent

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bird + arp
by Amadeus 26 Apr '12

26 Apr '12

Hi, is there any easy way right now to advertise host routes from kernel's arp table as soon as they appear? Best wishes Amadeus

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functions question
by Jaroslav Jirásek 18 Apr '12

18 Apr '12

Hello, I want to do function, which adds many communities in one function call now I use it like this: function add_community(pair peer_community) { bgp_community.add(peer_community); return true; } add_community((11111, 4444)) && add_community((11111, 5555)) && add_community((2222, 6666)) and I want to do something like this: function add_community(pair set peer_community) { bgp_community.add(peer_community); # doesnt work, incompatible types return true; } and call it like this: add_community([ (11111, 4444), (11111, 5555), (2222, 6666) ]) is it possible? Thank you Jirasek

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Re: Preserving device routes with kernel protocol
by Ondrej Zajicek 17 Apr '12

17 Apr '12

On Tue, Apr 17, 2012 at 11:37:52AM +0100, Howden Nick wrote: > Hi, > > I tried to post this to the mailing list but to no avail. Don't know why it wasn't delivered. > I wonder if you can shed some light on the problem we are having with > devices not being preserved when Bird updates the kernel routing tables. > >birdc show table BIRD > ... > 11.6.9.0/24 via 11.6.1.200 on TAP_One [MYOSPF 16:04] * I (100/10436) > ... > The BIRD table contains the correct network device TAP_One > >ip route ls table NEW > ... > 11.6.9.0/24 via 11.6.1.200 dev TAP_Two proto bird > ... > But, when we inspect the kernel table the network device information has > been lost. Generally, BIRD assumed that IP address is the whole key for gw and iface is derivable from it. With IPv6 and link-local addresses that had to changed, but it probably remained in some parts where it is not relevant to that. I personally never tested this variant. > Tap_One and Tap_Two both have IP addresses in the range 11.6.1.0/24 and I > am relying on the routing tables being correct in order to identify the > correct interface to use for the outbound traffic. The behaviour we are > seeing is the behaviour we expect if routes are added as: > ip route add 11.6.9.0/24 via 11.6.1.200 table NEW > instead of > ip route add 11.6.9.0/24 via 11.6.1.200 dev TAP_One table NEW You are right, for some unknown reason device is not used when route is propagated to the kernel. You could try attached patch. > My understanding was that the "device routes" option would allow the > device part of the routes to be preserved but there is clearly a flaw in > my knowledge. No, that 'device routes' is something completely different - whether device routes (routes without via/gw) are propagated. > Is it actually possible to preserve the device information present in the > BIRD routing tables when they are exported to kernel tables? Try attached patch. -- Elen sila lumenn' omentielvo Ondrej 'SanTiago' Zajicek (email: santiago(a)crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."

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BGP community not being set on outbound BGP updates
by Lex van Roon 11 Apr '12

11 Apr '12

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi All, I'm building a s/RTBH setup based on bird 1.3.7. I'm using a single route injector which has iBGP peerings with my route-reflector cluster. The setup looks like this (with the injector running on OpenBSD-4.9/Alpha and router* running on Debian Squeeze amd64 if that matters): [injector] / \ / \ / \ [router 1] [router 2] On the injector, I configure static routes, which I export over BGP. I want to tag these prefixes with a BGP community, so I can nullroute the IP's on my route-reflectors and all routers that are connected to this cluster. For this, I'm using the following configuration (only the relevant portions included): [injector] protocol static blacklist { route 1.2.3.4/32 via 192.0.2.1; } protocol bgp router_1 { local 172.16.0.1 as 65000; neighbor 172.16.0.2 as 65000; export filter { bgp_community = -empty-; bgp_community.add((65000,666)); accept; }; import none; } [router 1] protocol bgp injector { local 172.16.0.2 as 65000; neighbor 172.16.0.1 as 65000; export none; import filter { gw = 192.0.2.1; bgp_community = -empty-; bgp_community.add((65000,666)); accept; }; } The configuration for router 2 is identical apart from the IP's, so I haven't included this configuration. This setup works, however, the BGP community only gets set when the prefix enters BGP on router 1: user@injector# birdc show route 1.2.3.4/32 all BIRD 1.3.7 ready. 1.2.3.4/32 via 192.0.2.1 on lo1 [blacklist 12:01] * (200) Type: static unicast univ user@injector# birdc show route export router_1 all BIRD 1.3.7 ready. 1.2.3.4/32 via 192.0.2.1 on lo1 [blacklist 12:01] * (200) Type: static unicast univ BGP.origin: IGP BGP.as_path: BGP.next_hop: 192.0.2.1 BGP.local_pref: 100 user@router_1# birdc show route 1.2.3.4/32 BIRD 1.3.7 ready. 1.2.3.4/32 unreachable [injector 12:01 from 172.16.0.1] * (100) [i] user@router_1# birdc show route 1.2.3.4/32 all BIRD 1.3.7 ready. 1.2.3.4/32 unreachable [injector 12:01 from 172.16.0.1] * (100) [i] Type: BGP unicast univ BGP.origin: IGP BGP.as_path: BGP.next_hop: 192.0.2.1 BGP.local_pref: 100 BGP.community: (65000,666) My questions: 1) First, are these configuration snippets and command output enough to assist in these questions? 2) Is it possible to set a BGP community on a static route which is being exported over BGP? The example in the docs(*) says I should be able to do this. 3) Am i doing something wrong in this setup that is causing the BGP community not being set? 4) Is there a more intelligent way to get this to work? Imho, using a BGP community is the most cleanest and generic way to implement this, but I want this to be set on the injector, and not on my RR cluster. Kind Regards, Lex van Roon *) http://bird.network.cz/?get_doc&f=bird-6.html#ss6.1 - -- LRO-RIPE | 11FCBF2A | 756E 845C 0A88 75FF C750 1E7E 9723 E0DF 11FC BF2A -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJPfZxqAAoJEJcj4N8R/L8q5o8H/2bM1FIfXYtfMsTCsgF5VaeH /jWO1dvBDWpXd6bG/8LO786dboroOgF9u2nN8mMxJdkJ9eurlifs+VkPX53hoTiU 8nT4v1mjF7QzYu6pD3e4U6WDCuvmSSuKFt3F0DI0CBVEI3Gde9RFPT75rC2bfhu2 BOSx8dDmyOpS0WiMuQeqLmfZWwdK12lx7t2/AY1+F2IXCbhC1Q/4sEa8FOEKTLpT ZEPdTBL0N44dqcVaGtfg+FrmsIQi8iIiUrRFhFicxzzEuBuT5jvbbcPWroVg4Hco SSMD1ha9b4b4atWGY/kFa0ixO92aBMtEpJIsCoifd1TUPf3oNwawfjxJdEJkDiA= =y7xa -----END PGP SIGNATURE-----

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