Hello, we have 2 Cloud Core routers (the original 4GB RAM ones) which are configured almost identically providing the following functions:

PPPoE Server
DNS Server
Simple Firewall (Blocking P2P on forward chain and restricting access with about 10 input chain rules)
Small OSPF Area (Makes sure PPPoE clients with routed networks get their addresses routed to the correct Cloud)

The only difference between to two is really their addresses - they are sat on the same network and are basically just for redundancy. However, I've noticed that one router is constantly stuck at 1% CPU usage. The other sits at 0% even with 30-40 PPPoE clients connected .

Looking into it further, on Cloud2, there is a 'spi' process that is constantly using 1.3-1.5% of CPU (it actually has one core running at about 50%). I thought it may be something to do with the firewall as the only reference I can find is 'stateful packet inspection', but cloud1 does not show this process at all.

Does anyone know what this might be doing and if I can stop it? Considering our other cloud is doing exactly the same function and has no sign of this process I'm sure it shouldn't be active (or at least as active as it is).

Thanks,
Matt

I believe this one will be better asked directly to support@mikrotik.com
And please post back the reply here

Thanks leonset.

Usually big companies are near impossible to get help from directly as an end user, which is why I thought I'd ask in the forums. That doesn't appear to be the case with Mikrotik though .

They replied within minutes that this process is mainly involved with disk read/write and that the LCD can increase this if it's being pressed constantly.

We've had a minor issue with this Cloud since day 1 that the screen will never go off, although we've never thought much of it as it's not causing us any problems. Disabling the LCD completely instantly dropped the 1% CPU back to 0% so clearly there's a fault with our LCD that makes it think it's being used constantly. This is why it never goes off.

We now have a just a few cores running 1-4% each, just like cloud1 (which'll be mainly PPPoE I expect), giving an overall load of well below 1% (until we get a few hundred more sessions going)

SPI doesn't make me think about disk I/O, specially in a firewall router like a CCR... but besides the counter-intuitive of the name is nice to know what it was

SPI doesn't make me think about disk I/Owhat it was

http://en.wikipedia.org/wiki/Serial_Per ... erface_Bus

The SPI process is actually (I think) controlling the LCD screen. Per the link that Normis sent out one can see this in the article...

"Typical applications include Secure Digital cards and liquid crystal displays."