LAN - Ping timeouts 1 in ~300-400

[beengone]

I'm seeing 1 ping timeout in 300-400 pings on LAN. Simple network with a single unmanged switch, DSL modem/router, 4 machines. I'm pinging from machines to the router and from 3 of the machines to 1 of them. I'm seeing no losses to the router, but see 1 ping timeout in about 300-400 between a couple of the machines to the one. Sadly, this one machine runs a critical process.

What's my best way to troubleshoot this? The router's been restarted. That it happens so seldom seems odd.

 

[Samir]

Does this one ping break anything? I don't think I've seen a single ping that had completely zero loss. I hate to say it, but I think it's actually normal.

 

[beengone]

That's reassuring. This network has had many troubles and I'm preparing it for some big changes including a dedicated server. I want to be sure everything is reliable before I change anything. I was called in and found many drops wired incorrectly, multiple unmanaged switches, etc. Since I'm pinging a machine that also was not really set up correctly—all-day use by multiple users on the same admin account, freedom to browse all websites, etc.—I'm pretty confident these changes will fix most problems. Just wanted to be sure a drop now-and-then isn't an issue.

Thank you for setting me a little more at ease.

 

[Samir]

Now that you mentioned a little more about the computer's history, I'd run a netstat -a -b on it while it is idle. Check for connections it shouldn't have. If it's got malware on it, it may be causing the dropped ping and be indiciative of bigger problems.

But other than that, good luck cleaning up that mess! Been there, done that!