Hi all,
I'm writing to pick the collective mind on our conundrum. We have been in contact with Mikrotik support, due to a problem we are having in some of our networks (we're a small ISP in Kenya), where under 1400 to 2000 CPEs connected, over PPPoE, cause "flaps", where the CCR gets in a state where:
- PPPoE sessions get dropped
- RADIUS timeouts increase drastically, even though RADIUS is functioning fine (we use RADSEC)
- WebFig and Winbox both work, but all sections of the configuration are empty - no interfaces, no firewall rules, nothing
- Generating a supout.rif sometimes results in an "empty" file - it's still 5MB in size, but there is zero configuration details
- The CCR is unresponsive over API, SSH or telnet, where login prompts "freeze" after connection
The official answer from Mikrotik is, essentially, "you have run out of CPU".
Thus, I'd like to get people's views on:
- Are we really maxing out a CCR1072 with 1500-2000 PPPoE clients, each on a 4Mbps with burst to 5Mbps, each having a simple queue?
- Has anyone experienced the "freezing" issue before? It causes all traffic to drop at once, and slowly build up again over the course of 10 minutes or so
- Can anyone recommend PPPoE concentrators in the "low cost ISP" range?
We have contacted a couple of Mikrotik consultants who came up empty, if anyone has the experience and wants to take a stab at improving our configs & solving the issue, we're happy to setup a consultancy gig.