BGP 7.1 parameter DIbH ???

samyil · Fri Dec 10, 2021 9:58 am

Hi, I want to migrate to BGP version 7.1, but I have a problem with some rules. For example, I want to get a default route without anything else but I get prefixes with a DIbH parameter. This router is of course a test router, so it has the role of ibgp. What exactly is DIbH and how can I not get such prefixes?

My configuration:

/routing bgp template
add as=47453 disabled=no name=itservice router-id=93.155.130.38 \
    routing-table=main

/routing bgp connection
add address-families=ip as=47453 connect=yes disabled=no input.filter=bgp2-in \
    listen=yes local.role=ibgp name=bgp2 remote.address=93.155.130.61/32 .as=\
    47453 router-id=93.155.130.38 routing-table=main templates=itservice

/routing filter rule
add chain=bgp2-in disabled=no rule="set distance 2; accept;"
add chain=bgp2-in disabled=no rule="if (dst == 0.0.0.0/0) { accept; }"
add chain=bgp2-in disabled=no rule="reject;"

The result:

ip route/print
Flags: D - DYNAMIC; I, A - ACTIVE; c, s, b, y - COPY; H - HW-OFFLOADED
Columns: DST-ADDRESS, GATEWAY, DISTANCE
# DST-ADDRESS GATEWAY DISTANCE
DAb 0.0.0.0/0 93.155.130.61 2
DIbH 27.0.4.0/23 212.91.172.141 2
DIbH 50.3.152.0/22 93.155.130.66 2
DIbH 67.211.53.0/24 212.91.172.141 2
DIbH 75.75.232.0/22 93.155.130.66 2

Тhank you

samyil · Mon Dec 13, 2021 12:25 am

Why and only after reject I get prefixes ?
isn't the reject in version 7 the same filter as the discard in version 6 ?

routing/bgp/connection/print 
 1   name="bgp2" 
   [ .... ]
     input.filter=bgp2-in 
     
routing/filter/rule/print
add chain=bgp2-in rule="reject;"

mrz · Mon Dec 13, 2021 10:54 am

https://help.mikrotik.com/docs/pages/vi ... r-Commands

samyil · Sat Feb 12, 2022 7:38 pm

From help:

reject - reject matched prefix, the prefix will be stored in the memory as "filtered" and will not be the candidate to be selected as the best path.

Do I understand that the resulting prefix, whether filtered or not, always remains in memory? For example, I just want to get a default gateway because I don't have enough memory. My provider will fill in a complete table and my router will die. Isn't there an option to get only one prefix without any others in memory?

mducharme · Sun Feb 13, 2022 2:11 am

Isn't there an option to get only one prefix without any others in memory?

Yes there is, but not in /routing/filters. The option is under bgp, in "input.accept-nlri".

https://help.mikrotik.com/docs/pages/vi ... p/template

BGP 7.1 parameter DIbH ???

BGP 7.1 parameter DIbH ???

Re: BGP 7.1 parameter DIbH ???

Re: BGP 7.1 parameter DIbH ???

Re: BGP 7.1 parameter DIbH ???

Re: BGP 7.1 parameter DIbH ???

Who is online