Re: Giving a VPS a MAC address [message #3309 is a reply to message #1900] |
Mon, 22 May 2006 06:38   |
Jason Stubbs
Messages: 18 Registered: March 2006 Location: Japan
|
Junior Member |
|
|
I'm now running this setup in production combined with LVS to give complete failover and load balancing without any idle hardware. 
Now that there's a bit of traffic running over it though, overhead is a little more apparent. On a Xeon 2.4Ghz w/ HT (32bit/512kB cache), both the vtun client and server processes each use 1% CPU per 5MB (megabyte) / sec of bandwidth. That's taken when scp'ing a large file. Assuming packet size of 1460 bytes, that's about 4000 packets/sec. That gives about 200,000 packets/sec to exhaust a CPU. Likely a limit that won't be hit, but it does knock a small whole in the machine's computing power.
On the upside, I was afraid that with several tunnels being tied to the one bridge that all traffic would be sent across all tunnels making the above problem exponential. Luckily, Linux's bridging code seems to be smart enough to keep track of ARP replies and only send traffic where it needs to go.
[Updated on: Mon, 22 May 2006 07:01] Report message to a moderator
|
|
|