If you can see this check that
Your system environment is as follows:
- Machine A, eth0 10.0.1.1/24, eth1 10.0.2.254/24.
- Machine B, eth0 10.0.2.1/24
- Machine C, eth0 10.0.2.2/24
- Machine B and C are connected to eth1 on A via a switch.
- Machine B runs apache (and its pages use Oracle on C to run) and telnet.
- Machine C runs Oracle.
- Machine A also runs apache.
You have noticed that the traffic on A-eth0 has doubled, as has A-eth1.
Strangely, C is using 100% of the CPU time. B has higher than usual loading
of apache, but has a CPU running at 80% idle. What could be the problem?
|A.||B and C need to be moved to different physical networks.
|B.||The cgi programs on B have saturated Oracle on C with requests.
|C.||The network linking A,B, and C needs to be upgraded.
|D.||Apache on A is simply twice as popular as before.
|E.||The network on A is too slow to cope with the traffic.
There is no evidence to support this.
This is certainly a possibility.
As the CPU load has reached 100%, more network resources probably will not help.
This is reasonable, but does not explain what is happening with B and C.
With high CPU loads detected, it is likely that the traffic loads only one of the factors to consider.