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IP address scheme changeover

Today we're (I'm) changing over the rest of our servers to the new IP addressing scheme. This is noteworthy because we've only really done one so far - our Sharepoint box - and it broke a few unexpected things.

Reason? We are going to change all the IPs to a new subnet range to clean things up. We're halfway there, and now we can't get past ISA blocking RPC due to us trying to access different subnets, rather, go across subnets. Just doesn't work properly. Kinda silly.

Anyways, we had two options, make ISA disappear, or finish up the IP address change - something I was sure would break a lot of things.

So far, things are going pretty well, but I've set it up so we do everything easy first!

Changing the IP for the Exchange and BES servers is a little unnerving...but I think that Exchange pretty much exclusively uses DNS - I don't ever recall seeing statically set IP addresses, except in the TCP/IP settings. I've updated the static DNS records, so everything should work. Update: Yep, it works. AFTER you change the ISA rules to accommodate new IPs!!!

The SQL machines, however, I'm concerned about. There's a lot of custom stuff in there, and who knows what person decided an IP was a good way to connect something.
Update: Things seem to be working just fine so far....we'll see when people actually start using the system.

Changing the printers is proving to be the most difficult of all the changes. So far at least one of them is on a JetDirect box. It required a reboot before it would take the new IP settings, and now the server refuses to see that it's online. I may need to restart the printer itself.
Update: Server reboot fixed it.

Another thing to take into account on ISA is the network setup. If you remove the network/gateway ip from the old subnet, then try to access stuff on the old network - no connection until you re-add the network range and gateway ip!! Confused me for a minute...

Nmap is still turning up some random hosts, including an IP I'm sure that I have already disabled...nic is made by Accton Technology...and I'd thought it was on one of our Cisco devices, but the Cisco device no longer has that IP enabled, so this is messed up.
Update: Haha! Figured out what they were, and it's another lesson: Keep track of your network devices, and their respective logins!!!

We're working on a comprehensive document to keep better track of devices. We'll eventually tie it into something like Nagios.

Well, everything is up and running, so that concludes this entry. I'll post up any other oddities I run across.


  1. This is an useful information.I would like to share some points about IP address and IP changing.

    An IP address is also known as Internet Protocol Address.It is very important in Internet.Every Internet users are identify by their users using their IP address.IP address is Unique.You can get it from your Internet Service Provider[ISP].
    There are five classes of available IP ranges: Class A, Class B, Class C, Class D and Class E, while only A, B, and C are commonly used:
    Class A------------------> to
    Class B -----------------> to
    Class C -----------------> to
    Class D------------------> to
    Class E -----------------> to
    If your IP address is a static IP ,you cannot change it.
    If it is Dynamic IP address you can change it simply by resetting the modem.If you reset the modem the IP will change and a new IP assigned for you.

    To find your Internet IP address visit the site and get it.


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