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Ping to Gateway shows varies from 3ms up to 16ms - Should only be 1ms, right?

Hello Guy's,

Need some creative troubleshooting help here.  My boss is too cheap to pay for anything and can't spell I.T.

My environment -

I have a 4 3Com 4500 switch's in a stacked configuration.  I have a flat network, one VLAN.  I have a DMZ Vlan and a old Checkpoint FW.  The switch is the Gateway at .1  The FW is .254.

When I ping the gateway from the inside, my ping vaires from 3ms to 15ms but never at 1ms (I think it was at one point?)  When I ping the FW at .254 I get 1ms reply constant.  When I ping Yahoo or my ISP DNS server I get ping's of around 50ms up to 80ms or so...seems ok.

I have rebooted the switch many times.

What are my options of further troubleshooting this?  Again, I can't spend any money...any free tools?  Why would pinging the gateway be slower than pinging the the FW or any other host for that matter?

Does anyone know the 3com 4500 switch well?  Any logs I can search in there?

Thanks!
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JFrederick29
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Ok good to know!  Thanks for the quick response.
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jfrady

In addition - why are you using .1 (switch) as the gateway in a flat network?  All that's happening is that the switch is having to send ICMP redirects telling all your workstations to go through .254

If the switch were routing then it should be the default gateway.  If not it is just adding additional latency.

JFrederick is correct regarding the original question.  The switch doesn't think responding to ICMP echo's is it's primary job - as it should be.  Could also be that it is spending all it's time sending redirects.
But I have a ip route any to .254 statement in my 3com switch...so it should be routing.  Or are you taking about enabling RIP on the switch?
I understand.  Your switch has a default route pointed to the firewall.  All of your devices are using a default gateway of the 3Com switch, which isn't really the default gateway because the real gateway (firewall) is on the same layer 2 network.

So - every time a workstation send packets to it's default gateway they are re-directed to the firewall.

Unless I misunderstood your original post.  The only reason the 3Com switch should be the gateway is if the workstations are on a different subnet than the firewall and really need to be routed through the switch.  
yep...we were planning on doing VLAN's but never did cause the this product has a max of 3 IP Vlan's.

I'll be chaning the network around when we eventually get a newer FW.  Is there a problem though with the way it is now?  Could this cause any network problems?
Not necessarily any problems with the way it is currently.  Just not the most optimized way to do it.  If you are doing DHCP it would be an easy change that would be seamless to your users.  The current config will be causing some unnecessary ICMP traffic and a slight amount of latency.  Likely not enough to be noticeable though.  

If you're talking about the 4500 switch it supports many more than 3 VLAN's.  I'm pretty sure it's at least 255.
it does support many VLAN's but only 4 IP Interface VLAN's....talked to the 3com SE about this at length.
Interesting.  I was an SE at 3Com for a number of years.  I left a little after the 4500 came out but I seem to remember there was a limit of 5 IP addresses assigned to a single VLAN (multinetting).  But I don't remember the IP VLAN limit being anywhere near 3.  I could be wrong though.  I have a couple out in the garage I will try to test when I get a chance.