JNCIP- EBGP Regex-C1 and C2
what do expressions .*65010 and .*65020 do? would ^65010$ and ^65020$ not work?
and to filter default routes
instead of
route-filter 0.0.0.0/0 through 0.0.0.0/32 reject
route-filter 0.0.0.0/0 reject wouldn't work?
and to filter default routes
instead of
route-filter 0.0.0.0/0 through 0.0.0.0/32 reject
route-filter 0.0.0.0/0 reject wouldn't work?
Comments
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hoogen82
Member Posts: 272
.*65010 means you could ideally have 100 200 65010... but should have originated from 65010
^65010$ means only routes from 65010 and shouldn't have traversed any other AS.
There is a huge difference 0/0 through 0/32.. 0/0 means rejecting just about everything..Check the JNCIA page 162(196) in the pdf... They kind of explain it with examples...IS-IS Sleeps.
BGP peers are quiet.
Something must be wrong. -
IOS2JUNOS
Member Posts: 56 ■■□□□□□□□□
.*65010 means you could ideally have 100 200 65010... but should have originated from 65010
^65010$ means only routes from 65010 and shouldn't have traversed any other AS.
There is a huge difference 0/0 through 0/32.. 0/0 means rejecting just about everything..Check the JNCIA page 162(196) in the pdf... They kind of explain it with examples...
got it thanks..i was thinking if the import policy is applied to this customer peer then their routes would be coming from their AS only -
Aldur
Member Posts: 1,460
route-filter 0.0.0.0/0 reject wouldn't work?
keep in mind that you have to include a qualifier there too. For example if you said 0/0 orlonger then you'd block every single route, or if you said 0/0 exact then you'd only block 0/0 and 0/1, 0/2, etc could get through.
So 0/0 through 0/32 will block any 0.0.0.0 route no matter the prefix so that would be the best route to go."Bribe is such an ugly word. I prefer extortion. The X makes it sound cool."
-Bender -
IOS2JUNOS
Member Posts: 56 ■■□□□□□□□□
keep in mind that you have to include a qualifier there too. For example if you said 0/0 orlonger then you'd block every single route, or if you said 0/0 exact then you'd only block 0/0 and 0/1, 0/2, etc could get through.
So 0/0 through 0/32 will block any 0.0.0.0 route no matter the prefix so that would be the best route to go.
Thanks for explanation....i was under the impression that default route is only 0/0.. -
high1432007
Member Posts: 37 ■■□□□□□□□□
So 0/0 through 0/32 will block any 0.0.0.0 route no matter the prefix so that would be the best route to go.
Aldur, Can I understand in this way. rather than no matter ther prefix should it be mask?
which means will block prefix 0.0.0.0/0 or 0.0.0.0/24 or 0.0.0.0/32,
am I right? -
Aldur
Member Posts: 1,460
high1432007 wrote: »Aldur, Can I understand in this way. rather than no matter ther prefix should it be mask?
which means will block prefix 0.0.0.0/0 or 0.0.0.0/24 or 0.0.0.0/32,
am I right?
Oops, looks like I missed your question a few days ago.
Yup, I believe that your understanding is correct. The three prefixes that you listed will be blocked by the route filter 0/0 through 0/32."Bribe is such an ugly word. I prefer extortion. The X makes it sound cool."
-Bender
