Re: OSPFD + BGPD need to clarify behavior
Hi Claudio, Thank you for your help. Everything works as expected. Regards, Ivo Claudio Jeker wrote: On Thu, Jul 30, 2009 at 11:36:15AM +0300, Ivo Chutkin wrote: Hi Claudio and Insan, Thank you very much for clarified it. I have another question. Can I force the core to select only one border router as default and switch to the other in case it fails? Is there a point doing so, or I am better the way it is now? Increasing the OSPF metric on the backup router should give you that. __ Information from ESET NOD32 Antivirus, version of virus signature database 4300 (20090803) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Re: OSPFD + BGPD need to clarify behavior
Hi Claudio and Insan, Thank you very much for clarified it. I have another question. Can I force the core to select only one border router as default and switch to the other in case it fails? Is there a point doing so, or I am better the way it is now? Thank you, Ivo Insan Praja SW wrote: Hi, On Wed, 29 Jul 2009 14:38:43 +0700, Ivo Chutkin open...@bgone.net wrote: Hallo Misc, I need some general clarification about OSPF and BGP behavior. I have tow border routers, border1(OpenBSD4.4 - stable)and border2(OpenBSD4.4 -stable), and one core router, core1(OpenBSD4.5 - stable). Each border router talk eBGP(full feeds) with one upstream provider and have iBGP session between them. No problems here. If your cores advertise default route, they both valid to core. So, ECMP occured. The Core will randomly select default routes. There you go. See also netstat -nr and route -nv get default output. The two borders and the core have ospf session to each other in one area. Border routers redistribute default to core1. Core1 redistribute connected to borders. No problems here as well. I noticed something strange though. I start mtr to ibm.com for exampe, on the core1, I get different result every time I issue the command. See the attached results. First trace: HostLoss% Snt Last Avg Best Wrst StDev 1. border2 0.0% 20.3 0.3 0.3 0.3 0.0 2. border1 0.0% 20.8 0.8 0.8 0.8 0.0 3. 212.73.129.85 0.0% 14.1 4.1 4.1 4.1 0.0 4. 212.162.46.17 0.0% 12.6 2.6 2.6 2.6 0.0 5. ae-10-10.ebr1.Frankfurt1.Level3. 0.0% 1 31.6 31.6 31.6 31.6 0.0 6. ae-61-61.csw1.Frankfurt1.Level3. 0.0% 1 31.6 31.6 31.6 31.6 0.0 7. ae-62-62.ebr2.Frankfurt1.Level3. 0.0% 1 31.3 31.3 31.3 31.3 0.0 8. ae-44-44.ebr2.Washington1.Level3 0.0% 1 120.6 120.6 120.6 120.6 0.0 9. ae-62-62.csw1.Washington1.Level3 0.0% 1 124.2 124.2 124.2 124.2 0.0 10. ge-0-3-0-69.bbr1.Washington1.Lev 0.0% 1 121.1 121.1 121.1 121.1 0.0 11. so-1-0-0.mpls2.Raleigh1.Level3.n 0.0% 1 127.5 127.5 127.5 127.5 0.0 12. so-10-0.hsa2.Raleigh1.Level3.net 0.0% 1 126.5 126.5 126.5 126.5 0.0 13. IBM-GS-NA.hsa2.Raleigh1.Level3.n 0.0% 1 127.2 127.2 127.2 127.2 0.0 14. ??? Second trace: HostLoss% Snt Last Avg Best Wrst StDev 1. border2 0.0% 10.9 0.9 0.9 0.9 0.0 2. 212.36.5.217 0.0% 10.8 0.8 0.8 0.8 0.0 3. spectrum-ic-131757-ffm-b10.c.tel 0.0% 1 29.8 29.8 29.8 29.8 0.0 4. ffm-b10-link.telia.net0.0% 1 29.7 29.7 29.7 29.7 0.0 5. ffm-bb2-link.telia.net0.0% 1 29.6 29.6 29.6 29.6 0.0 6. prs-bb2-link.telia.net0.0% 1 42.0 42.0 42.0 42.0 0.0 7. ash-bb2-link.telia.net0.0% 1 121.4 121.4 121.4 121.4 0.0 8. 192.205.34.2090.0% 1 127.8 127.8 127.8 127.8 0.0 9. cr1.wswdc.ip.att.net 0.0% 1 164.2 164.2 164.2 164.2 0.0 10. cr2.phlpa.ip.att.net 0.0% 1 158.7 158.7 158.7 158.7 0.0 11. cr2.cl2oh.ip.att.net 0.0% 1 157.5 157.5 157.5 157.5 0.0 12. cr1.sl9mo.ip.att.net 0.0% 1 163.0 163.0 163.0 163.0 0.0 13. 12.122.142.29 0.0% 1 158.4 158.4 158.4 158.4 0.0 14. 12.125.74.74 0.0% 1 160.3 160.3 160.3 160.3 0.0 15. ??? The route is changed every time I issue the mtr command. It also happens with yahoo and probably many other. Is this behavior normal or there is something wrong with my configuration? I will send my config files to you, just let me know what you need. Also, I will provide any additional info you request. I really appreciate your help. Thank you, Ivo __ Information from ESET NOD32 Antivirus, version of virus signature database 4286 (20090728) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com Regards, __ Information from ESET NOD32 Antivirus, version of virus signature database 4289 (20090729) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Re: OSPFD + BGPD need to clarify behavior
On Thu, Jul 30, 2009 at 11:36:15AM +0300, Ivo Chutkin wrote: Hi Claudio and Insan, Thank you very much for clarified it. I have another question. Can I force the core to select only one border router as default and switch to the other in case it fails? Is there a point doing so, or I am better the way it is now? Increasing the OSPF metric on the backup router should give you that. -- :wq Claudio
OSPFD + BGPD need to clarify behavior
Hallo Misc, I need some general clarification about OSPF and BGP behavior. I have tow border routers, border1(OpenBSD4.4 - stable)and border2(OpenBSD4.4 -stable), and one core router, core1(OpenBSD4.5 - stable). Each border router talk eBGP(full feeds) with one upstream provider and have iBGP session between them. No problems here. The two borders and the core have ospf session to each other in one area. Border routers redistribute default to core1. Core1 redistribute connected to borders. No problems here as well. I noticed something strange though. I start mtr to ibm.com for exampe, on the core1, I get different result every time I issue the command. See the attached results. First trace: HostLoss% Snt Last Avg Best Wrst StDev 1. border2 0.0% 20.3 0.3 0.3 0.3 0.0 2. border1 0.0% 20.8 0.8 0.8 0.8 0.0 3. 212.73.129.85 0.0% 14.1 4.1 4.1 4.1 0.0 4. 212.162.46.17 0.0% 12.6 2.6 2.6 2.6 0.0 5. ae-10-10.ebr1.Frankfurt1.Level3. 0.0% 1 31.6 31.6 31.6 31.6 0.0 6. ae-61-61.csw1.Frankfurt1.Level3. 0.0% 1 31.6 31.6 31.6 31.6 0.0 7. ae-62-62.ebr2.Frankfurt1.Level3. 0.0% 1 31.3 31.3 31.3 31.3 0.0 8. ae-44-44.ebr2.Washington1.Level3 0.0% 1 120.6 120.6 120.6 120.6 0.0 9. ae-62-62.csw1.Washington1.Level3 0.0% 1 124.2 124.2 124.2 124.2 0.0 10. ge-0-3-0-69.bbr1.Washington1.Lev 0.0% 1 121.1 121.1 121.1 121.1 0.0 11. so-1-0-0.mpls2.Raleigh1.Level3.n 0.0% 1 127.5 127.5 127.5 127.5 0.0 12. so-10-0.hsa2.Raleigh1.Level3.net 0.0% 1 126.5 126.5 126.5 126.5 0.0 13. IBM-GS-NA.hsa2.Raleigh1.Level3.n 0.0% 1 127.2 127.2 127.2 127.2 0.0 14. ??? Second trace: HostLoss% Snt Last Avg Best Wrst StDev 1. border2 0.0% 10.9 0.9 0.9 0.9 0.0 2. 212.36.5.217 0.0% 10.8 0.8 0.8 0.8 0.0 3. spectrum-ic-131757-ffm-b10.c.tel 0.0% 1 29.8 29.8 29.8 29.8 0.0 4. ffm-b10-link.telia.net0.0% 1 29.7 29.7 29.7 29.7 0.0 5. ffm-bb2-link.telia.net0.0% 1 29.6 29.6 29.6 29.6 0.0 6. prs-bb2-link.telia.net0.0% 1 42.0 42.0 42.0 42.0 0.0 7. ash-bb2-link.telia.net0.0% 1 121.4 121.4 121.4 121.4 0.0 8. 192.205.34.2090.0% 1 127.8 127.8 127.8 127.8 0.0 9. cr1.wswdc.ip.att.net 0.0% 1 164.2 164.2 164.2 164.2 0.0 10. cr2.phlpa.ip.att.net 0.0% 1 158.7 158.7 158.7 158.7 0.0 11. cr2.cl2oh.ip.att.net 0.0% 1 157.5 157.5 157.5 157.5 0.0 12. cr1.sl9mo.ip.att.net 0.0% 1 163.0 163.0 163.0 163.0 0.0 13. 12.122.142.29 0.0% 1 158.4 158.4 158.4 158.4 0.0 14. 12.125.74.74 0.0% 1 160.3 160.3 160.3 160.3 0.0 15. ??? The route is changed every time I issue the mtr command. It also happens with yahoo and probably many other. Is this behavior normal or there is something wrong with my configuration? I will send my config files to you, just let me know what you need. Also, I will provide any additional info you request. I really appreciate your help. Thank you, Ivo __ Information from ESET NOD32 Antivirus, version of virus signature database 4286 (20090728) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Re: OSPFD + BGPD need to clarify behavior
On Wed, Jul 29, 2009 at 10:38:43AM +0300, Ivo Chutkin wrote: Hallo Misc, I need some general clarification about OSPF and BGP behavior. I have tow border routers, border1(OpenBSD4.4 - stable)and border2(OpenBSD4.4 -stable), and one core router, core1(OpenBSD4.5 - stable). Each border router talk eBGP(full feeds) with one upstream provider and have iBGP session between them. No problems here. The two borders and the core have ospf session to each other in one area. Border routers redistribute default to core1. Core1 redistribute connected to borders. No problems here as well. I noticed something strange though. I start mtr to ibm.com for exampe, on the core1, I get different result every time I issue the command. See the attached results. :~ host ibm.com ibm.com has address 129.42.18.103 ibm.com has address 129.42.16.103 ibm.com has address 129.42.17.103 :~ bgpctl show rib 129.42.16.0/22 all flags: * = Valid, = Selected, I = via IBGP, A = Announced origin: i = IGP, e = EGP, ? = Incomplete flags destination gateway lpref med aspath origin I* 129.42.16.0/24 62.153.202.177 100 1000 3320 3356 14904 16807 i I* 129.42.17.0/24 62.153.202.177 100 1000 3320 701 15006 16807 i I* 129.42.18.0/24 62.153.202.177 100 1000 3320 3356 2140 16807 i I* 129.42.19.0/24 62.153.202.177 100 1000 3320 3356 14904 16807 i It resolves to three different IPs in three different networks connected to three different upstreams no wonder the trace is different every time. -- :wq Claudio
Re: OSPFD + BGPD need to clarify behavior
Hi, On Wed, 29 Jul 2009 14:38:43 +0700, Ivo Chutkin open...@bgone.net wrote: Hallo Misc, I need some general clarification about OSPF and BGP behavior. I have tow border routers, border1(OpenBSD4.4 - stable)and border2(OpenBSD4.4 -stable), and one core router, core1(OpenBSD4.5 - stable). Each border router talk eBGP(full feeds) with one upstream provider and have iBGP session between them. No problems here. If your cores advertise default route, they both valid to core. So, ECMP occured. The Core will randomly select default routes. There you go. See also netstat -nr and route -nv get default output. The two borders and the core have ospf session to each other in one area. Border routers redistribute default to core1. Core1 redistribute connected to borders. No problems here as well. I noticed something strange though. I start mtr to ibm.com for exampe, on the core1, I get different result every time I issue the command. See the attached results. First trace: HostLoss% Snt Last Avg Best Wrst StDev 1. border2 0.0% 20.3 0.3 0.3 0.3 0.0 2. border1 0.0% 20.8 0.8 0.8 0.8 0.0 3. 212.73.129.85 0.0% 14.1 4.1 4.1 4.1 0.0 4. 212.162.46.17 0.0% 12.6 2.6 2.6 2.6 0.0 5. ae-10-10.ebr1.Frankfurt1.Level3. 0.0% 1 31.6 31.6 31.6 31.6 0.0 6. ae-61-61.csw1.Frankfurt1.Level3. 0.0% 1 31.6 31.6 31.6 31.6 0.0 7. ae-62-62.ebr2.Frankfurt1.Level3. 0.0% 1 31.3 31.3 31.3 31.3 0.0 8. ae-44-44.ebr2.Washington1.Level3 0.0% 1 120.6 120.6 120.6 120.6 0.0 9. ae-62-62.csw1.Washington1.Level3 0.0% 1 124.2 124.2 124.2 124.2 0.0 10. ge-0-3-0-69.bbr1.Washington1.Lev 0.0% 1 121.1 121.1 121.1 121.1 0.0 11. so-1-0-0.mpls2.Raleigh1.Level3.n 0.0% 1 127.5 127.5 127.5 127.5 0.0 12. so-10-0.hsa2.Raleigh1.Level3.net 0.0% 1 126.5 126.5 126.5 126.5 0.0 13. IBM-GS-NA.hsa2.Raleigh1.Level3.n 0.0% 1 127.2 127.2 127.2 127.2 0.0 14. ??? Second trace: HostLoss% Snt Last Avg Best Wrst StDev 1. border2 0.0% 10.9 0.9 0.9 0.9 0.0 2. 212.36.5.217 0.0% 10.8 0.8 0.8 0.8 0.0 3. spectrum-ic-131757-ffm-b10.c.tel 0.0% 1 29.8 29.8 29.8 29.8 0.0 4. ffm-b10-link.telia.net0.0% 1 29.7 29.7 29.7 29.7 0.0 5. ffm-bb2-link.telia.net0.0% 1 29.6 29.6 29.6 29.6 0.0 6. prs-bb2-link.telia.net0.0% 1 42.0 42.0 42.0 42.0 0.0 7. ash-bb2-link.telia.net0.0% 1 121.4 121.4 121.4 121.4 0.0 8. 192.205.34.2090.0% 1 127.8 127.8 127.8 127.8 0.0 9. cr1.wswdc.ip.att.net 0.0% 1 164.2 164.2 164.2 164.2 0.0 10. cr2.phlpa.ip.att.net 0.0% 1 158.7 158.7 158.7 158.7 0.0 11. cr2.cl2oh.ip.att.net 0.0% 1 157.5 157.5 157.5 157.5 0.0 12. cr1.sl9mo.ip.att.net 0.0% 1 163.0 163.0 163.0 163.0 0.0 13. 12.122.142.29 0.0% 1 158.4 158.4 158.4 158.4 0.0 14. 12.125.74.74 0.0% 1 160.3 160.3 160.3 160.3 0.0 15. ??? The route is changed every time I issue the mtr command. It also happens with yahoo and probably many other. Is this behavior normal or there is something wrong with my configuration? I will send my config files to you, just let me know what you need. Also, I will provide any additional info you request. I really appreciate your help. Thank you, Ivo __ Information from ESET NOD32 Antivirus, version of virus signature database 4286 (20090728) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com Regards, -- insandotpraja(at)gmaildotcom
