March 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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bird under heavy cpu load
by Oleg 07 Apr '12

07 Apr '12

Hi, all. I have some experience with bird under heavy cpu load. I had a situation when bird do frequent updates of kernel table, because of bgp-session frequent down/up (because of cpu and/or net load). I waited about 5-10 minutes for birdc started, when i wanted to reconfigure bird with configure soft command from birdc(ssh and other interactive programs works well). After i changed bird.conf in such a way that i get from upstream 0.0.0.0/0 instead of full view birdc worked fine and bird cpu load lowered(before, bird load cpu about 30-89%). What can i do in such situtation in future for birdc normal work? And additional two questions: Does bird immediately push routes info in kernel table, if it receive routes updates from bgp-peer or it wait for the next kernel table scan? How can i set in one kernel protocol different scan time from another one? Thanks.

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Criating a static route in a filter or function.
by Kalil de A. Carvalho 29 Mar '12

29 Mar '12

Hello all. It is possible create a static route in a filter or function? If yes, could anyone gave me a example? Best regards. -- Kalil de A. Carvalho CCNA

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Implementing RTBH filtering / BGP tagging
by Gregg Berkholtz 28 Mar '12

28 Mar '12

In working to streamline our utilization of each upstream's RTBH filtering mechanisms (e.g. http://www.he.net/adm/blackhole.html ), I'm having a heck of a time configuring BIRD to "mirror" Cisco product behaviors. Here's the Cisco Way (where X.X.X.X is the ip to blackhole): conf t ip route X.X.X.X 255.255.255.255 Null0 router bgp YourAS network X.X.X.X mask 255.255.255.255 route-map blackhole route-map blackhole permit 10 set community 6939:666 end What I believe needs to happen w/ BIRD, and the Linux Kernel route tables: 1) Create and maintain a non-default Linux kernel route table, to accomplish blackholing at our gateways (working great). Also wanting to have BIRD to monitor this non-default route table, and :666 tag+announce upstream any /32 entries within our 199.127.224.0/22. 2) BIRD imports the non-default kernel route table (seems to be working ok). 3) For each "protocol bgp *Upstream*", use an export filter to identify and tag relevant "blackhole" route entries with a specific RTBH community (e.g. 6939:666)...this is what I'm struggling with. While snippets are below, our entire bird.conf (minus comments) can be found at: http://pastebin.com/xE1AxtGe Here's my breakdown of what seems to be happening: 1) Create/edit/update the non-default kernel route table (works great, the Linux kernel/route config drops this traffic without issue): "... ~$ sudo ip rule add from all table 10 priority 10; sudo ip route add blackhole 199.127.225.73/32 table 10; ..... ~$ sudo ip route show table 10 |wc -l 456 ~$ sudo ip rule 0: from all lookup local 10: from all lookup 10 ..." 2) Read the non-default kernel route table (from bird.conf): "... table blackroutes; protocol kernel blackhole { table blackroutes; kernel table 10; scan time 10; learn; import all; export all; } ..." BIRD seems to import the non-default kernel table without issue: "... ~$ sudo birdc show protocols all |grep blackhole -C 10 blackhole Kernel blackroutes up Mar17 Preference: 10 Input filter: ACCEPT Output filter: ACCEPT Routes: 454 imported, 0 exported, 454 preferred Route change stats: received rejected filtered ignored accepted Import updates: 1363 0 0 0 1363 Import withdraws: 909 0 --- 0 909 Export updates: 1363 1363 0 --- 0 Export withdraws: 909 --- --- --- 0 ~$ sudo ip route show table 10 |wc -l 456 ..." BTW: the bulk of our "blacklist" entries come from http://www.spamhaus.org/drop/drop.lasso, although we only want to tag+announce what we control (e.g. /32's within 199.127.224.0/22). 3) Can't seem to figure out correct tagging method/commands (from bird.conf): "... filter bgp_out_he { if (proto = "blackhole" ) then { bgp_community = -empty-; bgp_community.add((6939,666)); } if net ~ [65.49.94.0/24] then accept; if net ~ [199.127.224.0/22] then accept; reject; } ... protocol bgp HE { local as 14613; source address 65.19.175.14; neighbor 65.19.175.13 as 6939; import all; ... export filter bgp_out_he; } ..." Am I missing something obvious? Going about this the wrong way? Thanks greatly for any help, Gregg Berkholtz

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Distributing default route dynamically through OSPF / passive interfaces
by Thomas York 28 Mar '12

28 Mar '12

I am looking to replace Quagga with Bird for our OSPF deployment. Currently, we have all of our plants with PtP links (either through PtP T1s or OpenVPN links). We use static routes to get the tunnels and such up, then distribute routes (including a default route) via OSPF (using costs to designate a primary interface). This works great currently. However, Quagga has terrible OSPFv3 support (especially with distributing a default route) so I'm looking to move to Bird. I have two VMs configured with 2 dummy interfaces per (to simulate two routers-on-a-stick). One of the routers has a default route set on one of its dummy interface (router1, dummy0). I have routes being distributed back and forth without issue. However, I can't seem to get router1 to distribute its default route to router2. Below are some IPs and sample configs. My other issue is that there isn't a passive directive for OSPF (at least, according to the documentation). I would like to prevent the accepting/broadcasting of OSPF data on the dummy interfaces. Is there an easy way to do this without firewalling? Thanks! IPs - http://pastebin.com/iA7z5mhP Bird.conf for router1 - http://pastebin.com/xDCvsARL Bird.conf for router2 - http://pastebin.com/nxxSREef --Thomas York

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One router - Two ASN
by Miłosz Oller 27 Mar '12

27 Mar '12

Hi How can I run two asn on one router? Example: ISP1 | --------------- | AS1 - AS2 | --------------- | ISP2 ISP1 is connected to AS1, ISP2 is connected to AS2. How can I configure connection AS1-AS2 with bgp protocol on localhost (neighbor ip and source address)? -- Miłosz

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Probe neighbor
by Kalil de A. Carvalho 27 Mar '12

27 Mar '12

Hello list. I'm new BIRD user and I'm going to test at company where I work. I know the BGP has the ability to test if neighbor is working or not. But I want to make a filter or function to detect if the neighbor is up or down and this test it's running all time. Anyone has ideia if is possible. If yes, could tell me who can I do that? Thanks a lot.

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