invalid subnet mask set 255.255.255.255

  • Thread starter Thread starter Mike Brearley
  • Start date Start date
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Mike Brearley

I have a device that the vender is telling me the only way to change it's
network settings is by telnetting into it. They have a program that can
connect via serial to 'view' it's settings, but that it, just view.

Subnet mask has somehow been set to 255.255.255.255. IP is 10.103.1.40,
gateway is 10.103.1.8.

Is there anyway to get into this via telnet? Specific ip/subnet/gateway
settings I'd need to set on the pc connecting to it?

I've tried setting an ip of 10.103.1.41 and a range of different subnet
masks, but nothing let me even ping the device. The only thing that gives
me hope is that after pinging it, its MAC address shows in my arp table.

Any help would be greatly appreciated.

--
Posted 'as is'. If there are any spelling and/or grammar mistakes, they
were a direct result of my fingers and brain not being synchronized or my
lack of caffeine.

Mike Brearley
 
I highly doubt anyone will have experience with this particular device,
that's why I asked the question as a generic network question and not device
specific. It's a RS232 LAN Converter from Westerstrand Time Distribution
out of Sweden. My vender first had this issue with the first lan converted
they sent. They replaced that one and after I received the new one, I set
my settings, saved them, then couldn't access the device anymore (just like
what happened with my vender on the first device). After about 2 weeks of
very very slow email conversation, they finally gave me a propgram that
could read the settings through a serial connection. That's when I noticed
the invalid subnet mask. And the thing is... I never touched the subnet
mask when I was setting it up for our network as it was already correct
(255.255.255.0).

I'll try the forum you suggested, but still would like help here as well if
anyone out there can help.

--
Posted 'as is'. If there are any spelling and/or grammar mistakes, they
were a direct result of my fingers and brain not being synchronized or my
lack of caffeine.

Mike Brearley
 
Thanks for the follow-up. I checked the website and only found a
minimal amount of documentation on the device - just a simple PDF
product spec and environmental doc. Maybe someone at BB-Rpts
can help.
 
Should use the mask 255.255.255.0. You could also try using a cross-over
cable and connect to it.
 
I know that the subnet mask should be 255.255.255.0, I'm not sure what
happened to set it to the invalid entry. I've tried a cross-over cable,
nothing is working.

Thanks...

--
Posted 'as is'. If there are any spelling and/or grammar mistakes, they
were a direct result of my fingers and brain not being synchronized or my
lack of caffeine.

Mike Brearley
 
I'm assuming this is a routing or switching device. Have you considered
simply replacing it with a device you know you can access?
 
Have you tried connecting it and a single PC to a small hub or via crossover
cable and then used Ethereal to see any traffic on the hub as the device
powers up to see if any other protocols are in use? You might be able to
reset back to factory defaults and then do this step to see what is
unlocked by default.

When doing this with a Windows PC or notebook remember to unbind everything
except TCP/IP from the network adapter or you'll have to wade through the
windows networking traffic as well.

Chris
 
Haven't tried ethereal, but I do have it on my computer. I'll have to try
that Monday (2 minutes to quiting time for the weekend :-)

I have connected to a small hub on a single PC and also tried a cross-over,
so when I get in on Monday, I'll do that again and run ethereal.

There is no reset on the device, if there was, I probably wouldn't be
posting here... :-)

Have a great weekend.

--
Posted 'as is'. If there are any spelling and/or grammar mistakes, they
were a direct result of my fingers and brain not being synchronized or my
lack of caffeine.

Mike Brearley
 
Yes, but my vender has already replaced one that they screwed up (or rather
that the device screwed up on them by doing the same thing it did to me).
Now the manufacturer is hesitant on just sending a third device. It's an
RS232 to LAN converter from Westerstrand out of Sweden.

--
Posted 'as is'. If there are any spelling and/or grammar mistakes, they
were a direct result of my fingers and brain not being synchronized or my
lack of caffeine.

Mike Brearley
 
Sorry just no magic here.

Unfortunately the device now doesn't think anything but itself is on it's own network, and it can't reach the configured gateway
because that isn't on the LAN either (with that mask the LAN is now defined as just itself).

If you can't talk to this thing from the serial side I can't see how you're ever going to get communicating with it using TCP/IP.
(You see the MAC because that's a no-address broadcast operation.)

You should try a factory reset. Since you don't have a manual and nobody knows a d**m thing, unplug it, hold in whatever buttons
there are, power it back on and keep the button pressed for 10 seconds. If that isn't possible or doesn't work, you have to open it
up and look for a jumper or battery to pull - something along those lines. There's always a way. Think of it as a puzzle. Once it is
reset you can configure yourself on to it's default network and communicate with it.

Best of luck

Steve Duff, MCSE, MVP
Ergodic Systems, Inc.
 
With this subnet mask, there are no available host IPs on the subnet.
Neither the assigned IP or the assigned gateway have any meaning here, as
this piece of equipment will not be talking to anything.

Does this device have a reset switch or a CMOS-clear jumper (or battery) to
pull out? Or is there as serial console connection that you can use to talk
to the device with?
 
There's no reset switch, no jumpers, no battery. There is a serial
connection (as it's an rs232 to rg45 lan converter), but with it's current
firmware rev, the companies new program that allows settings the network
settings through the serial connection will not work. My vender is flashing
a new chip and is sending it to me to arrive tomorrow. With that, I should
be all set (I hope).

--
Posted 'as is'. If there are any spelling and/or grammar mistakes, they
were a direct result of my fingers and brain not being synchronized or my
lack of caffeine.

Mike Brearley
 
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