Limitation of BNG-SRG state control routes

[Serg_tsk]

Dear colleagues, I have new question about Subscriber redundancy group.

ASR 9006, RSP440-SE, iOS-XR Version 6.4.2, 32-bit.

What is the maximum number of entries in state-control-route directive I can use ? I read this topic:

"A maximum of 30 state control routes can be added in each subscriber redundancy group (SRG), with a limit of 10 state control routes for each route type. That is, user can have a maximum 10 IPv4 routes, 10 IANA routes and 10 IAPD routes in each SRG. In these 30 routes, user can have routes in either the default or the non-default VRF"

But i have more that 30 entries in my running-config and that is OK: SRG works normally.

subscriber
 redundancy
  group 24
   preferred-role master
   virtual-mac 10f3.1117.0024
   slave-mode hot
   hold-timer 5
   peer 172.24.63.2
   peer route-disable
   access-tracking srg_cluster24
   state-control-route ipv4 10.211.4.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.5.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.6.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.4.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.5.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.6.0/24 vrf cust tag 1
   state-control-route ipv4 10.103.70.0/24 vrf cust tag 1
   state-control-route ipv4 10.185.69.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.20.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.26.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.27.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.75.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.91.0/24 vrf cust tag 1
   state-control-route ipv4 10.243.99.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.20.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.26.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.27.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.75.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.91.0/24 vrf cust tag 1
   state-control-route ipv4 172.17.99.0/24 vrf cust tag 1
   state-control-route ipv4 10.115.115.0/24 vrf cust tag 1
   state-control-route ipv4 10.117.189.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.131.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.137.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.139.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.141.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.142.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.143.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.145.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.146.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.147.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.151.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.158.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.162.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.167.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.168.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.169.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.170.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.171.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.176.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.184.0/24 vrf cust tag 1
   state-control-route ipv4 10.161.189.0/24 vrf cust tag 1
   state-control-route ipv4 10.174.196.0/24 vrf cust tag 1
   state-control-route ipv4 10.174.207.0/24 vrf cust tag 1
   state-control-route ipv4 10.211.126.0/24 vrf cust tag 1
   state-control-route ipv4 10.227.196.0/24 vrf cust tag 1
   state-control-route ipv4 10.227.203.0/24 vrf cust tag 1
   state-control-route ipv4 10.227.207.0/24 vrf cust tag 1
   state-control-route ipv4 10.227.219.0/24 vrf cust tag 1
   state-control-route ipv4 10.227.244.0/24 vrf cust tag 1
   state-control-route ipv4 10.243.100.0/24 vrf cust tag 1
   state-control-route ipv4 10.243.120.0/24 vrf cust tag 1
   state-control-route ipv4 10.243.124.0/24 vrf cust tag 1
   state-control-route ipv4 10.245.170.0/24 vrf cust tag 1
   state-control-route ipv4 172.19.69.0/24 vrf cust tag 1
   state-control-route ipv4 172.19.70.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.115.0/24 vrf cust tag 1
   state-control-route ipv4 172.16.126.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.131.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.137.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.139.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.141.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.142.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.143.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.145.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.146.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.147.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.151.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.158.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.162.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.167.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.168.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.169.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.170.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.171.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.176.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.184.0/24 vrf cust tag 1
   state-control-route ipv4 172.18.189.0/24 vrf cust tag 1
   state-control-route ipv4 172.20.170.0/24 vrf cust tag 1
   state-control-route ipv4 172.21.189.0/24 vrf cust tag 1
   state-control-route ipv4 172.17.100.0/24 vrf cust tag 1
   state-control-route ipv4 172.17.120.0/24 vrf cust tag 1
   state-control-route ipv4 172.17.124.0/24 vrf cust tag 1
   state-control-route ipv4 172.23.196.0/24 vrf cust tag 1
   state-control-route ipv4 172.23.207.0/24 vrf cust tag 1
   state-control-route ipv4 172.22.196.0/24 vrf cust tag 1
   state-control-route ipv4 172.22.203.0/24 vrf cust tag 1
   state-control-route ipv4 172.22.207.0/24 vrf cust tag 1
   state-control-route ipv4 172.22.219.0/24 vrf cust tag 1
   state-control-route ipv4 172.22.244.0/24 vrf cust tag 1
   revertive-timer 7 maximum 9
   interface-list
    interface Bundle-Ether24.0 id 240
    interface Bundle-Ether24.1 id 241
   !
  !
 !
!

Thank you!

With best regards, Sergey.

[xthuijs · Accepted solution]

hi sergey, it is more a testing limit,

I see your ranges are quite disjoint and not easy to summarize, but if they can be summarized, I would recommend to do so.

alternatively, you can use the null route option with object tracking enabled on them to redistribute these static routes, it is a bit less user friendly since you need the rpl to exclude other possible static routes you may not want to redistribute, where as the subscrbier state control route give you a natural tracked semi static route of the subscriber kind with a tag that is easier to trap through RPL without much extra config of prefix lists etc.

xander

[Serg_tsk]

Thank you ,Xander. I'll use non-summarized routes until we migrate to S-C-tag subscriber termination and /32 mask per subscriber.

With best regards

Sergey.

[Carlos A. Silva]

I'm going to cross my fingers real hard and see if anyone reads this.

I have a scenario where multiple access-devices (OLTs) in different physical interfaces would (desired) point to a single subnet (ipv4 unnumbered) and a single BGP advertisement. I can't think of a way to make it work with geored and ONE single prefix, other than splitting that single prefix into smaller ones and configuring each smaller prefix into different groups, so that when one single OLT has to switchover, only that advertisement moves from one BNG to the other. Correct?