It's late night here... excuse my typos and all the gibberish.. But yeah Static routes maybe the only solution..
-Hoogen On Sun, Nov 8, 2009 at 2:29 AM, Hoogen <[email protected]> wrote: > What is your topology?.. Is your topology is similar to the book?? The > questions do seem a bit awkward... Well yeah NSSA def route is like an > external route so changing the value affects everything... and for ISIS > level 1 preference can be set specifically and def route generated by ISIS > (Book Case Study) is level 1. > > Thinking about it... The only way you can do things is using preference > values.. since OSPF nor ISIS can have an import policy. So in this scenario > of yours you might not have optimal routing.. It is a loop..if you do have > to put that level 1 external preference as 149... > > Another way to just solve your problem would be to have static routes... to > the ABR's. > > -Hoogen > > > On Sun, Nov 8, 2009 at 12:38 AM, Walaa Abdel razzak <[email protected]>wrote: > >> Hi >> >> If I did this, then R6 or R7 will prefer datacenter routes through R5 bcoz >> they r coming with lower preference than ISIS routes which make sub-optimal >> routing. >> >> >> Best Regards, >> Walaa Abdel Razzak >> >> >> -----Original Message----- >> From: Hoogen [mailto:[email protected] <[email protected]>] >> Sent: Sat 07/11/2009 22:38 >> To: Walaa Abdel razzak >> Cc: [email protected] >> Subject: Re: [j-nsp] ISIS-OSPF Redistribution Questions >> >> Hi, >> >> Your scenario looks like a complete opposite of what we have in the case >> study, from what you have mentioned here.. The solution would be that on >> R6 >> and R7 you set the ospf external-preference to be lower than 149.. This >> would make the def route from OSPF more preferred. >> >> set protocols ospf external-preference 148 <-- Make the nssa def route >> preference on R6 and R7 to be lower than that received from the ISIS DC >> router. >> >> -Hoogen >> >> 2009/11/7 Walaa Abdel razzak <[email protected]> >> >> > Hi Experts >> > >> > >> > >> > If you have area 2 nssa receiving default route from the ABR with metric >> > 150, two routers R6, R7 are sending this default route to ISIS level 1 >> > router in the DC. The L1 external preference are modified on R6, R7 to >> be >> > 149. This is to prefer routes coming from ISIS than OSPF. The problem is >> > that DC router resend the default route from R6 to R7. R7 see it with >> > preference of 149 and the default route is coming from OSPF is 150 so it >> > prefers the ISIS which cause non-optimal routing. Any ideas to solve >> this >> > issue without making modification on the DC router? >> > >> > >> > >> > Sample config: >> > >> > >> > >> > R6 or R7 config.: >> > >> > -------------------- >> > >> > isis { >> > >> > export senddefault; --------à send default to the ISIS >> router >> > >> > level 2 disable; >> > >> > level 1 external-preference 149; >> > >> > interface fe-1/3/1.23; >> > >> > interface lo0.6; >> > >> > } >> > >> > ospf { >> > >> > export fromisis; --------à redistribute routes from >> ISIS >> > >> > area 0.0.0.2 { >> > >> > nssa; >> > >> > interface lo0.6; >> > >> > interface fe-1/3/0.20; >> > >> > interface fe-1/3/1.16; >> > >> > interface fe-1/3/1.23 { >> > >> > passive; >> > >> > } >> > >> > } >> > >> > } >> > >> > >> > >> > DC: >> > >> > ----- >> > >> > isis { >> > >> > export static-isis; >> > >> > level 2 disable; >> > >> > interface fe-1/3/0.23; >> > >> > interface fe-1/3/0.24; >> > >> > } >> > >> > >> > >> > BR, >> > >> > Walaa Abdel Razzak >> > >> > _______________________________________________ >> > juniper-nsp mailing list [email protected] >> > https://puck.nether.net/mailman/listinfo/juniper-nsp >> >> > _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp
