I have several identical servers:
CPU iCore7-2700K (3,5Ghz 4 core), MB Intel DQ67OW, Server Lan Adapter PCI-E 4x Dual (i82576).
Servers have identical configuration.
The only difference is that one of them uses L2TP tunnels, on the other PPTP.
The problem - the server with PPTP has a higher load on the CPU. At the same time - traffic is 2.5 times less.
In the hours of highest load - observed degradation of service (reduced speed, increase delay).
As you can see on screenshot, for some reason the process of “firewall” has more value, even though I tried to completely disable the firewall rules
DDoS is not found
I tried the version MikroTik ROS 5.15, 5.17, 5.19 - no difference
Hardware is exactly the same
If the difference is only in the PPTP and L2TP, why the process of “Firewall” in the “top” takes more resources, not ppp / pptp?
All these manipulations did not bring positive results - in the evening (when most users) - CPU very high = degradate service (just something 100 Mbps of traffic).
Similar servers hardware and setting (but L2TP, not PPTP) = all rights (more than 300 mbit/s, more 1000 L2TP tunels 20-30% CPU max.)
reason of PPTP ? )))))
Who knows?
P.S. May be need full reinstall ROS - as Windows ? )))))))
