Opinions on a new network I have inherited


Diamond Member
Oct 10, 1999
Hi guys,

I haven't posted here in a really long time but definitely could use some opinions and advice on a new job and network I have inherited. I started recently and Monday I would like to present some ideas to my boss, the CTO.

The previous network/systems admin and IT manager was terminated on October of this year. I had to find this out via the company's Windows AD server and it had the reason in his profile description, nobody told me anything other than he was no longer with the company.

The network consists of a fiber connection from Comcast which is metered, a few Cisco 3750 switches, a 2950, a Cisco Wireless controller feeding two APs, and various other misc networking equipment. This is all at the office I work at, not including other sites. There is also a Cisco ASA dishing out an encrypted VPN that is working but needs further config polishing which the CTO specifically told me about on my first day.

The server infrastructure consists of many Windows 2008 R2, and many 2012 / R2 servers. I haven't seen any 2016 ones yet. They all run under VMWare for the most part. I am relatively new to VMWare but I haven't really had a problem learning the VM side of things. They don't seem to have any Linux servers, which is a shame as I have a lot of experience with them. They also have a SAN which I believe is EMC that they use for Veeam backups. However, it looks like the Veeam VM is down? *sigh*

Now to my question. So far I haven't been doing much other than attempting to document the network and servers in a spreadsheet. I have been given a non demanding task of adding a network device to the network for a vendor. I have gotten what I would believe to be the obvious gateway and DNS servers and probable subnet mask, but I am clueless on what IP to assign without a possible IP conflict.

The servers room has many cables that are not labeled, none are bundled together, and they do not have any tools such as a Fluke to test where cables are ran.

So, the next day I work I plan to address this with the CTO. I believe he already knows what I plan to ask, but I will need a Fluke cable tester to label all the devices. As for the routers and switches, I may need a rolled cable to log into each switch (if I can't telnet to them) to get the latest config files for documentation purposes. From there I can get all the local subnet and VLAN information. The configuration files they have saved are from MANY years ago and I am certain devices have been added. All of the ports do not have descriptions, except for maybe a half dozen. I will probably log into each Windows Server to find which one is dishing out DHCP to find that IP pool.

Does anyone have any other things they would do (ie, network discovery tools you can use on Linux like nmap) that could be used on the Windows side to easily find the IPs/subnets/etc that are on the network? Once I get into the main router I should be able to just do show cdp neigh to gather most if not all the Cisco devices, but I may not even have the password(s) to them!

I have had many corporate IT jobs whether it be from the networking or sys admin side, but never something of a cleanup role like this before I can even add something new to the network. And the vendor is specifically asking for the public/outside IP. For all I know, they are all being NAT'd from a static IP from the Comcast fiber connection. That isn't much of a worry, I can figure that out pretty easily.

Thanks in advance for any input! For being such a small company, the salary here is the highest of any job I have gotten yet, and I have a promise from the CTO that he will be promoting me to IT Manager once he has "groomed me for management" which will have another salary bump. He has a lot of IT management experience and I would really like to follow through and show him I am the best at what I do. I'm trying to figure out how to do that without saying "your last IT manager didn't document everything and now I have to put all the puzzle pieces together even to add something new to the network".

I'm also a bit rusty as I haven't had a network / systems role in a while, which I'm sure doesn't help but it does give me a fresh perspective on their network and systems.

So literally any and all opinions, including "dude you're SOL" are welcome. :)
Last edited: