Topic: Latency too high?

[del]

I have an SME server in server/gateway mode installed in a medical office and the company that is providing the software for the medical records have done their network check and are saying that the latency is 70ms and needs to be 50ms or lower. Of course the ISP is saying that there is no problem their end so I am now in a position where I need to "check" the server. Can someone point me in the right direction. If I log in as root and type ping microsoft.com it just hangs and eventually times out. Is this the correct command to ping an external IP address? The internet is a 1.5mbs T1 line and everything else seems to be working fine. Any help is much appreciated.

Regards,
Del

[cactus]

If I log in as root and type ping microsoft.com it just hangs and eventually times out. Is this the correct command to ping an external IP address? The internet is a 1.5mbs T1 line and everything else seems to be working fine. Any help is much appreciated.

That is the proper command normally.

Did you already test that the internet connection works by using the option from the admin console? Please login as admin and choose the appropriate option from the menu to check your internet connection.

Can you describe the network topology from your SME Server to the internet connection you are using? Are there any firewalls/gateways in between? Perhaps you can draw a simple diagram?

[idp_qbn]

Hi del,
The command (ping) is good, it is the site that is wrong. They probably have blocked ping requests - many sites do that.
Try pinging somewhere else. eg ping bbc.co.uk or tpg.com.au

When I have connection  troubles, I start with:
1) ping localhost [127.0.0.0]
2) ping my router
3) ping ISP
4) ping bbc.co.uk

I just check in that order - if one works, then I move down the list until it fails

[mmccarn]

What tool is the software vendor using for their test, and where are they testing to?

It does you no good to worry about your network if the problem is elsewhere (I had one vendor wait until after roll-out to tell a client in Amsterdam that the system wouldn't work from their office due to their latency - with the server in the US!)

Once you know what tool they're using, you can try running the same test.

The "standard" version of "PingPlotter" is free, and will give you a nice picture of the times between hops from your location to an off-site location: http://www.pingplotter.com/download.html

PingPlotter quickly tells me that from my office I can talk to "www.google.com" in about 10ms, but that talking to "www.bbc.co.uk" takes 80 - 90 ms.  It also tells me which hop introduces the big delay when talking to the bbc.

If the software vendor doesn't believe the results, configure a computer with the SME server's internet settings, plug it directly in to your WAN connection, and re-run the test from there.

On my SME server:
- The first hop reported is my SME LAN IP
- I think the second hop reported is the near end of my PPP (DSL) connection, but it could be the far end.
- The third hop is definitely at my ISP


You can get the same information in a more text-y mode by running "traceroute" from the SME server itself.

[idp_qbn]

Hi again
I have just seen the reply from cactus. If you can get access to the server (either sitting at the server itself or using PuTTY) his solution is quickest and simplest.
And mmcarn givesa good advice as well. Must get a copy of PingPlotter!

My method gives an indication of where the problem may be and also gives the time for responses, which is what the latency issue is about.

Good luck
Ian

[del]

That is the proper command normally.

Did you already test that the internet connection works by using the option from the admin console? Please login as admin and choose the appropriate option from the menu to check your internet connection.

Can you describe the network topology from your SME Server to the internet connection you are using? Are there any firewalls/gateways in between? Perhaps you can draw a simple diagram?

I have no problems getting on the internet through the test internet option when logged in as admin. My server is in server/gateway mode and the internet connection is a T1 connected to the first ethernet card, this is by way of a cat 5 cable from the T1 providers box, so there are no firewalls or routers involved, the server acts as both for the local network. The software company are testing remotely from there offices, I am not sure how, I have emailed and asked them to explain how they are running their tests and where to. I will repost when I get this info. Thanks for all the input and suggestions so far.

Regards,
Del

[mmccarn]

The software company are testing remotely from there offices

This tells us that they're running some sort of test from their office to your SME.

So, if you can get the IP address of their office, you can test the same route in reverse using the tools described earlier.

You might get the IP of their office by getting the IP address of their mail server (nslookup -type=MX their-email-domain.com, or sometimes by looking at the headers for an email message from them to you, or (if necessary), by asking