CCR1036 - 50% cpu usage

RouterOS General
1

I have a pair of CCR1036-12G-4S running for about a year now, running 6.40.8 with firmware 3.41.

Today one of them is showing a constant 50% CPU usage instead of the normal 3-4%, but traffic levels are low, currently around 2-4Mbit/s and 500-1000 pps.

/tool profile
NAME CPU USAGE
console 0%
firewall 0%
networking 44.3%
management 0%
routing 2.5%
profiling 0.5%
unclassified 3.1%
total 50.4%

There are also three gre/ipsec tunnels which won’t come up (ipsec is successful but gre stays down).

Not sure where to look now to find out what might be wrong, other than to try rebooting. Any ideas?

2

OK this is a Bug in Router OS.

We hit exactly the same thing. The Tile based Mikrotik’s have a bug in the “bugfix” release of RouterOS that cayuses the ipsec process to crash and the router will run at about 50% CPU.

To fix this - UPGRADE to the current release rater than bugfix.

This was cause by Mikrotik re-writing the RouterOS to support IKE V2…

3

Oh wow, that was quick, thanks. This makes sense, only a few weeks ago I changed one of the tunnels to be ikev2. For now I will switch back to ikev1. I suppose it will need a reboot to resolve the problem.

4

Should not matter, you must upgrade ROS. The bug takes out all IPSEC (no matter IKE v1 or 2).

Upgrade to current and the issue goes away.