Hello colleagues!
When working with the CCR2004 router, I encountered the following problem, an abnormally large and uneven load on the processor cores.
Information about the router is on the first screenshot.
On this router, there is a termination /25 network that is ananosed via BGP, BGP sessions with 2 borders are also raised (upstream provider)
Also, in addition to 4 sessions on this router, there are 20 constantly active BGP sessions and 19 L2TP VPN sessions (respectively, L2TP Server is raised on this router)
The router announces via BGP to each VPN tunnel addresses on /32 of the /25 subnet that is located on this router.
There is no NAT on the router, there is no traffic marking, Fastreack is enabled, IPSEC is not used in VPN, only mschap2 is used for authentication. Allow Fast Path is enabled.
I revised the firewall, I don’t see any problems, there is a rule for filtering traffic on port 53.
I encountered some problems in the operation of this scheme, namely, at most locations there are 2 communication channels and they are 100/100 mb everything works well on them, but there are locations where there are 2 communication channels 1000/1000 mb and problems appear on them.
When I run an iperf tcp or udp test at a location where the communication channels are 100/100, then everything works well, it shows the guaranteed speed, if I repeat the same test at a location where the communication channels are 1000/1000 Mb, then all BGP sessions are switched on the router, in the logs in this moment only messages about reconnection of VPN and BGP sessions.
An uneven load of processor cores was noticed (screenshots at the very beginning) at peak moments, the load is 1.2GB
By network interfaces, the router has a bond of 2x SFP +, it is possible to rush it up to 4x SFP +, but I don’t know if this will give any effect regarding load balancing.
After reading a lot of information on various forums, I found a lot of recommendations regarding rebooting the router, namely its complete de-energization and after that the load on the cores is distributed evenly, I have not done this yet, I decided to consult with you to hear your opinion about this decision.
In the release notes I saw that in ROS7 there are cardinal changes in the system core, this raises the question: will the upgrade to ROS7 help in terms of load balancing across processor cores.
I would be very grateful for your help and comments, if I did not provide enough information, tell me what else needs to be specified.
