Hi Question 4 routers (CCR's), each has connection to Internet vlan. each connect to a ISP. call them a b c d. there is a vrrp on the internet vlan which is used as dgw. receiving full table from ISP, so somehere between 800k-1.2M prefixes. I go onto router a and disable the isp link. I can see inbound slowly peeter off The interesting things is that the DGW disappears from the route table on router A, but routers B,C,D still have all the prefixes advertised from the ISP connected on router A, still in their routing table. so packet hit the VRRP and then get routed to router A, it has a iBGP DGW and sends it back to router B,C,D, they check routing table and send it back to router A. loop . death. took about 3 min for the routes to be pulled from the routing table in B,C,D. How can I make this/convergence work faster, can I ? Alex
The way I used to get around this was to not carry a full table. Each router would filter the accepted routes to default route, and one or two AS hops on each ISP. Then I preferenced my cheapest transit provider as the best default route. Convergence was MUCH faster :) On 4 May 2017 at 10:42, Alex Samad <alex@samad.com.au> wrote:
Hi
Question
4 routers (CCR's), each has connection to Internet vlan. each connect to a ISP. call them a b c d.
there is a vrrp on the internet vlan which is used as dgw.
receiving full table from ISP, so somehere between 800k-1.2M prefixes.
I go onto router a and disable the isp link.
I can see inbound slowly peeter off
The interesting things is that the DGW disappears from the route table on router A, but routers B,C,D still have all the prefixes advertised from the ISP connected on router A, still in their routing table.
so packet hit the VRRP and then get routed to router A, it has a iBGP DGW and sends it back to router B,C,D, they check routing table and send it back to router A. loop . death.
took about 3 min for the routes to be pulled from the routing table in B,C,D.
How can I make this/convergence work faster, can I ?
Alex _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
-- Damien Gardner Jnr VK2TDG. Dip EE. GradIEAust rendrag@rendrag.net - http://www.rendrag.net/ -- We rode on the winds of the rising storm, We ran to the sounds of thunder. We danced among the lightning bolts, and tore the world asunder
Just for the archives I reduced my prefixes to just ones I wanted, so around 10K prefix and convergence is less than 1s - time to flip screens. There seems to be some sweet spot cause around 30k is back to 2 mins.. Alex On 4 May 2017 at 10:58, Damien Gardner Jnr <rendrag@rendrag.net> wrote:
The way I used to get around this was to not carry a full table. Each router would filter the accepted routes to default route, and one or two AS hops on each ISP. Then I preferenced my cheapest transit provider as the best default route.
Convergence was MUCH faster :)
On 4 May 2017 at 10:42, Alex Samad <alex@samad.com.au> wrote:
Hi
Question
4 routers (CCR's), each has connection to Internet vlan. each connect to a ISP. call them a b c d.
there is a vrrp on the internet vlan which is used as dgw.
receiving full table from ISP, so somehere between 800k-1.2M prefixes.
I go onto router a and disable the isp link.
I can see inbound slowly peeter off
The interesting things is that the DGW disappears from the route table on router A, but routers B,C,D still have all the prefixes advertised from the ISP connected on router A, still in their routing table.
so packet hit the VRRP and then get routed to router A, it has a iBGP DGW and sends it back to router B,C,D, they check routing table and send it back to router A. loop . death.
took about 3 min for the routes to be pulled from the routing table in B,C,D.
How can I make this/convergence work faster, can I ?
Alex _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
--
Damien Gardner Jnr VK2TDG. Dip EE. GradIEAust rendrag@rendrag.net - http://www.rendrag.net/ -- We rode on the winds of the rising storm, We ran to the sounds of thunder. We danced among the lightning bolts, and tore the world asunder _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
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Alex Samad -
Damien Gardner Jnr