spectrum48k

We have a LAN of 20 users, most of which use DHCP leases from the Win2k server

Currently the scope is 192.168.0.51 - 100

I need to move it to 192.168.0.101 - 200

Leases expire after 7 days

Obviously I don't want to cause any disruption to the users, so what's the best approach to get this done ?

For example, am I right in thinking I can change the scope immediately, and let the leases naturally expire after which they'll obtain leases on the new scope ? This, I'd hope, wouldn't interrupt anyone?

Sonic'

As long as its the same subnet it shouldn't make any difference or cause any disruption

spectrum48k

perfick!

Bodgit

you can delete the leases in use. this will not cut them off but when they reboot they will get an ip address from the new scope.

spectrum48k

When trying to change the scope I'm getting

"the specified range either overlaps an existing one or is invalid"

I'm trying to change it to 192.168.101 to 192.168.0.199 with 255.255.255.0

is there a command or tool that shows all the ip addresses in use on the LAN ? Perhaps there's a rogue device using an ip address in the scope I want to use?

Sonic'

IIRC you have to delete the old scope and then create the new scope, you cant create a new scope that overlaps with one already created

Shouldn't matter about devices already in use on the network

spectrum48k

but no IP addresses are overlapping ?

spectrum48k

but no IP addresses are overlapping ?

eg.

Currently the scope is 192.168.0.51 - 100
I need to move it to 192.168.0.101 - 200

Sonic'

Have you got any exclusions set up ? you could try removing all the addressess from the active leases, but then the devices still switched on will probably just renew again

spectrum48k

Ok, I manually deleted all the leases and deleted the scope, then created a new one and it did the trick.

Thanks Sonic - can you tell me what you think of the following...

Instead of using the Win2k Server's own DHCP server, I think I'd feel a lot more assured if I used the DHCP server on the SonicWall firewall appliance instead, as I feel it's probably a more reliable device than the old Win2k server to be honest. Do you think it would be ok to do this ?

Sonic'

Can you add options on the SonicWall one for things like DNS etc, and if using AD will it integrate with AD and update DNS as and when clients get new ip addressess ?

Just something to bear in mind, (mind you Windows isnt that good at keeping DNS upto date with DHCP ) ive been in many a situation whereby we have kept Novell's DHCP server instead of switching to the Windows one

spectrum48k

ah, good point - there's no integration with AD, AFAIK

I'll stick with Windows for now.

Thanks Sonic, great info.

spectrum48k

I've activated the new scope. Is there something I need to put in scope options, as its now not issuing any DNS info to clients ?

eg. I've added the dns entries
for route,r do I specifiy the LAN's gateway ?
time server ?

mannyo

Yes, you need to configure all those under the scope options,

DNS servers (primary/secondary)
Default gateway,
DNS domain name.

no need for time server.

spectrum48k

cheers

whats the difference between:
005 name servers
006 DNS servers ?

(win2k server > DHCP server > server options)

ChrisB

I can't give you a technical explanation of the difference, but use 006 DNS.

spectrum48k

I did!

thanks all

apalmer

iTrader: (8)

Mate

Option 005 is legacy, the "Internet Name Server" standard was the direct predecessor of DNS for FQDN name resolution, not NetBios. Scenarios where both were implemented and both seen to be working were probably in environments where segmented or multuple layerd lans were not used as
IEN-116 uses different ports to communicate with the name servers listed ports 42tcp i think and 42udp, whereas DNS communications use 53UDP for unreliable communication You use TCP also!

Stick with 006 as this is the correct option for the DNS standard

You should be able to dig up an RFC for the reasons behind its demise.

spectrum48k

I'll take your word for it!