Problem connecting to a WebConsole

[John Waller]

I hope somebody can explain this one for me.

Up until a couple of weeks ago we have been using a Secure WebConsole attached to a HP9000 without a problem, then the network guys installed a couple of switches.

A couple of days ago when I tried to connect it failed and said it couldn't find it. I tried a ping which also failed.

I performed a factory reset and re-configured it but I still couldn't connect from my PC, but when I opened up a telnet connection to another UNIX system which we have set as the default gateway a ping worked.

Further investigation has shown, which ever IP address we configure as the default gateway will work but no other.

The Network Configuration is as follows

I.P Address 172.17.144.30
Subnet Mask 255.255.240.0
IP Gateway 172.17.144.5

As a bit of further information I have found that it will work if I do not configure a IP Gateway but I have been running for about a year with an IP gateway set with no problems.

An suggestions or explanations will be gladly received.

[Stephen Bouzan]

From the info you gave your network can have over 4000 hosts, but is the Web Console on the same network? You might need to add a route statement to your host to the Web Console.

Have you tried a traceroute to see at which device the packets are being dropped. From what you describe it is difficult nail it down. Can you be more specific about what your host ip is and the Web Console ip. What about the network guys, they should be able to explain why you cannot ping your console.

[John Waller]

Ok Stephen, A quick general layout of our network.

172.17.144.xxx IP addresses are used for UNIX servers and equipment

172.17.152.1 - 172.17.156.254 used by PC's / Printers (DHCP allocated)

172.17.151.xxx. - Temporary equipment

It makes no difference from which range I choose an Ip from I still can't get a ping from any device except the one configured at the Default IP gateway.

I tried the network guys and they don't believe me. They are convinced I have made an error in setting up the WebConsole but as long I am using IP addresses in the above ranges and a 255.255.240.0 subnet, what mistake can I make?

[John Waller]

A trace route is not helping because it I try from a normal PC it just says "No response", if I configure the WebConsole so the IP gateway is that of the PC it just goes straight to the IP address without going to any other device.

[Andrew Maslin]

Are there any filters set up on the switches?

Have you tried connecting to the web console from a machine connected to the same physical hub? That brings up another question - are these switched hubs that were installed, or do you have hubs connected to switches? We have some switched hubs with VLANs set up, and the filters and settings for the ports in the hubs have to be correct for there to be proper connectivity.

I agree with you, it doesn't sound like a web console problem to me.

Just to be safe, have you double-checked your datacomm settings? I still don't think this would cause what you're describing, but it's worth checking.

[Charles Harris]

John, this sounds like a bit of a strang one, but from what I can gather from your descriptions, it sounds like the web consoles aren't being seen on the network.
Asuming that each console is on the same ip range as the server it is connected to, can you ping your console from the server? - If you can't then the default gateway cannot see the device from where it is. This could be caused by the port on the switch being disabled or your network guys doing a um job on their switch routing tables / protocol / port mappings.

Have you tried running traceroutes from your server the console is connected to and your pc to see if the end hop before your console is the same ? - If it is, the last hop either doesn't know about your console's address on the lan (network chaps to check their arp tables from the switches to see if the web console's is there) or the final hop knows nothing of the next gateway in your journey to the console.

Either way, this is very unlikley to be the web console it's self. I'd get you networks crew to try and ping the address from their switches to prove connectivity.


Hope this is of some use!


-ChaZ-

[Charles Harris]

John, this sounds like a bit of a strang one, but from what I can gather from your descriptions, it sounds like the web consoles aren't being seen on the network.
Asuming that each console is on the same ip range as the server it is connected to, can you ping your console from the server? - If you can't then the default gateway cannot see the device from where it is. This could be caused by the port on the switch being disabled or your network guys doing a bum job on their switch routing tables / protocol / port mappings.

Have you tried running traceroutes from your server the console is connected to and your pc to see if the end hop before your console is the same ? - If it is, the last hop either doesn't know about your console's address on the lan (network chaps to check their arp tables from the switches to see if the web console's is there) or the final hop knows nothing of the next gateway in your journey to the console.

Either way, this is very unlikley to be the web console it's self. I'd get you networks crew to try and ping the address from their switches to prove connectivity.


Hope this is of some use!


-ChaZ-

[John Waller]

Andrew - In responce to your questions, No, I am assured by the network people that there are no filters set on the switches , plus I have disconnected a known working device and plugged the webconsole into the same that port and still I couldn't ping from anything except the server configured as the IP Gateway. The Data Comms settings seem OK , just the Standard 9600 stuff.

Charles - As I mentioned ealier above, A traceroute is not helping, from a non working device it just says "No response", and from any device which I configure as the IP gateway, it just goes there and straight back, no other hops involved.

Does anybody know of some free software I can put on my PC to monitor the network so I can try to identify what the WebConsole is sending out and to where ?

Many thanks for your time so far.

[Charles Harris]

Re the network sniffing. I used to use a few, depending on your platform. For windows nt, you can get the network monitor, which comes with some of the NT admin stuff, wether it's free or not I don't know.

Nmap for linux is fairly good, it may help determin if you switches are blocking etc...

[Charles Harris]

Just thought, Nessus is more of an ESM but it can also be quite handy for exploring networks + flaws and runs under windows or Linux and it's GNU!


Here:-

http://nessus.org

[John Waller]

Many thanks for the information about the network sniffers Charles, but it's turned out to be a Firmware issue on the WebConsole. This was a old unit with a A1.4 firmware rev. I don't know why it stopped working but an upgrade to A1.9 has fixed the problem. The funny thing is I have found another unit with A1.4 firmware which also does not work anymore.

[Charles Harris]

Firmware!?!?! - oh well, I'll get my coat!!!

-ChaZ-