MT as a pppoe server

newtonek · Fri Feb 09, 2007 12:44 pm

Pentium 4D 2,8GHz, 512 Ram dual e1000 net adapter. My problem is high load - when i have about 500 sessions active i get about 90% of cpu usage. On pppoe interfaces i have simple queues added. All works with from remote radius aaa. Generally my question is about load - is this level of cpu usage is normal?

HarvSki · Fri Feb 09, 2007 2:00 pm

Does the performance of the network degrade? if not then no worries, you could add a 2nd server to the same ethernet collision domain then PPPoE sessions would be distributed between them.

newtonek · Fri Feb 09, 2007 2:13 pm

Earlier I had 3com eth cards, load was 100% - bad things happen ;> I'm thinking about second machine, but I think that this one shoud easily handle 1000 sessions :/ So I'm asking if someone has similar configuration to compare loads.

HarvSki · Fri Feb 09, 2007 3:03 pm

So what type of cards are you using now? Intel server ones are best I've found so far and are what others have also reported as good, I have had good success with Compaq (intel chipset) NICs bought from eBay

newtonek · Fri Feb 09, 2007 3:21 pm

Intel dual port server adapter pci-e (e1000).

weller · Fri Feb 09, 2007 7:19 pm

newtonek, set Change TCP MSS to no to reduce CPU utilization

newtonek · Fri Feb 09, 2007 11:17 pm

newtonek, set Change TCP MSS to no to reduce CPU utilization

I don't understand ;p
Change TCP MSS is set to yes

hci · Fri Feb 09, 2007 11:28 pm

Pentium 4D 2,8GHz, 512 Ram dual e1000 net adapter. My problem is high load - when i have about 500 sessions active i get about 90% of cpu usage. On pppoe interfaces i have simple queues added. All works with from remote radius aaa. Generally my question is about load - is this level of cpu usage is normal?

Under "Queue", "Queue Types" what is your default queue type? If its not pfifo I would change it to pfifo.

We use Intel PRO/100 network cards integrated on Supermicro P4 motherboards. Around 500 PPPoE sessions per server and no noticeable CPU load.

Matt

busa1300 · Fri Feb 09, 2007 11:30 pm

"Change TCP MSS" is a setting in your ppp profile

newtonek · Fri Feb 09, 2007 11:31 pm

I've had pfifo, now it't bfifo for test. Same load. When ypu have 500 sessions what's your load, what machine? You have simple queues on ppp interfaces?

hci · Sat Feb 10, 2007 12:02 am

Its not peak time now. 337 active connections doing a total about 5mbps between them all. Most are set at 512kbps. PPPoE automatically adds the queues.

system resource> print
uptime: 3w5d1h28m49s
version: "2.9.39"
free-memory: 335892kB
total-memory: 387076kB
cpu: "Intel(R)"
cpu-frequency: 2499MHz
cpu-load: 9
free-hdd-space: 10307012kB
total-hdd-space: 10365292kB
write-sect-since-reboot: 48490720
write-sect-total: 372666360

Matt

newtonek · Sat Feb 10, 2007 12:24 am

I have about tx 25 rx 12 Mbps. Maby this is the case.

hci · Sat Feb 10, 2007 12:38 am

Hmm, could be. Use Mikrotik firewall to drop all p2p and see if the problem goes away. ;<) You might try a couple of good quality Intel NIC's. Likely only 30$ a piece so cheap to try.

http://www.newegg.com/Product/Product.a ... 6833106123

Before ordering anything make sure Mikrotik supports the model.

Matt

newtonek · Sat Feb 10, 2007 12:41 am

Users pay to suck ;] I have very good NIC - Intel dual port gigabit server adapter. Dropping p2p is not possible :/

weller · Thu Feb 22, 2007 10:44 pm

in your PPP profiles, set Change TCP MSS to no for all profiles assigned to your users (secrets), this will reduce CPU utilization to a significant level

abab_rafiq · Fri Feb 23, 2007 10:30 am

newtonek, set Change TCP MSS to no to reduce CPU utilization
I don't understand ;p
Change TCP MSS is set to yes

Set your TCP MSS from ip > firewall > mangle.

choose forward chain
protocol = tcp(6)
tcp flags = syn
action = change MSS
new TCP MSS = 1400

Rafiq...
http://forum.linux.org.bd

newtonek · Tue Feb 27, 2007 2:24 pm

Hmm. It may really work, now i have about 30% load. I'll see in the evening.