Plug A into Hole B
by David July
Archived Article (2001–2014) 
Although when I was hired I understood a good portion of my job would be technical support issues and the like, I was a bit too optimistic that it would not transfer into a majority situation. Over the past month I have been diagnosing several issues with our network and websites. Today alone I had four different conversations with the Network Operations Centre that manages our T-1 circuit. I had to research and learn what a T-1 Multiplexer was and learn how to reconfigure it. I am still not done either because I am having trouble accessing the DHCP server to reconfigure it as well. Oh, well. It keeps everyone happy which keeps those direct deposits a flowing.
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You are the company's computer guy. You might just have to accept that as your lot in life. While you write the great american novel on the side of course.
...while sitting in the grass under big oak trees taking pictures in between chapters. Yeah, I guess that is not a bad compromise.
Multiplexers are why not everyone can get DSL while sitting in the grass under big oak trees.
We have two of them: TSU 120.
I'm not real familiar with high-end network equipment, but I think we've got one of those in the IS lab that is the backbone of our network. Pretty cool.
I have always been more of a software guy myself and am quickly remembering why that is the case. It is not that I cannot learn or that it is too difficult, but I really am not a fan of having to deal a lot with physical stuff when it comes to computing, hence why my only personal computer is a laptop.
Steven: Any suggestions for sniffing out a DHCP server on a peer-to-peer network? I have one IP address (which ipconfig does not list as the DHCP server) that has an HTTP interface, though it does not fully identify itself (nor do I have the usernames and passwords). Use of a packet sniffer and other tools I like did not reveal anything informative.
Strictly speaking its no longer a peer-peer network if you have a centralized piece of equipment like a DHCP server, however, its all in how you want to slice and dice the same apple, or orange if you prefer.
It's a little hard to give advice on such things without a clear view of the picture, what works, what doesn't etc.
Is this new equipment being installed or pre-existing equipment being reconfigured?
Does this network function at all at the moment? If so what can you use it for and what is it not doing that it should. Can you share files, but not access the internet etc.
Are the machines on the network not capable of obtaining IP addresses? If so, are they choosing them for themselves like, 169.*.*.* etc. Or are they set to static? Is there a NAT involved in this mess?
I recommend in this type of situations, if possible, connecting one computer as directly to the plexer as possible, going through as few other routers/switches/etc as possible and taking everyone else offline, while you try and sort this out. This should of course be done after hours, if the network is at all functional now.
You also mentioned you have one IP from one machine at might be the server, is it in the same subnet as that machines IP?
It also may be an issue of how many IP's you have allocated to your network by the server. If they are all leased out, can't get more, etc.
Feel free to give me a call.
Yeah, I think I might just do that. Once I give you more specifics I think you will have a much better understanding of the situation. We will talk more about it later. Thank you for your input as always.