Tag Archives: fixed ip address

why do some people insist on using fixed ip addresses, instead of dhcp?

Computer Aid Posted on by

Within one week, I’ve had 2 customers (both businesses), who have called me out to fix a network issue… and in both cases, the problem was due to a network that had a mixture of dhcp-assigned IP addresses, and fixed IP addresses.

In one case, the entire network of over 15 PCs were setup by another company… All with fixed IP addresses (and no one keeping track of the IP addresses)… a recipe for disaster, but too many PCs for me to quickly switch over to DHCP in just a few minutes… I guess I’ll need to wait until the customer sees the need to change to DHCP.

The other customer was more annoying: I initially setup the 5 PCs to use DHCP… and at some point, somebody decided that two PCs were better off using a fixed IP address (but the router hadn’t been changed to remove those IP addresses from the DHCP pool…). After many network dropouts, and duplicate IP address problems, I was called out and eventually tracked down the problem… Whats really annoying, is that it was so unnecessary.

problem with fixed IP addresses

Computer Aid Posted on by

A customer had problems connecting 2 PCs to the office network. The last time I was there (about 3 months ago), all the PCs worked well on the network.

I take a look at the XP PC and vista laptop, and I notice that they are on a different workgroup to the rest on the office. There is an Office workgroup, and an msoffice workgroup… so I make them all msoffice.

The vista laptop still has problems though… sometimes it can see the internet, but cannot see any network shared drives… other times its the other way around…

I look at the TCP/IP settings, and I see its using a fixed IP address. I’m trying to think of a reason why a PC would be changed from DHCP to fixed IP addresses… but all I can come up with, is someone changed it due to their limited network knowledge, while attempting to fix another problem.

Anyway, once back to dhcp, its all running normally again.

But a few days later, I’m called back, as another vista laptop is now acting up.

I take a look, but it has DHCP enabled.

The owner says he sometimes gets a message about a duplicate IP address.

OK, looks like I’ll need to check all PCs, looking for which ones have been switched over to fixed IP addresses.

It turns out just 1 PC (the main file server) needed to go back to DHCP. 30 minutes later, everything is working smoothly again.

The only potential problem, is a network printer that was installed a while back. The printer tech did all the work… and I was never involved… if the printer uses a fixed IP address, then its a potential “timebomb”.

Next time I’m called out, I’ll take a look at the settings, and if needed, I’ll setup the network router to allocate a fixed IP address to the printer.