RAS server using too many DHCP IP addresses.

[Ralph]

I have had a RAS server set up on 2K server for several years.
Sometime around January I started running out of DHCP assigned
addresses. I traced it to the 4 RAS servers I have that are also
running 2K server. I have about 40 extra DHCP assinged addresses. I
looked for a solution but just reduced the lease time to get around
it. No major changes have been made to the network except for MS
patches and updates. Can anyone explain why this recently started to
occur and if there is a fix? I used to have a lease time of 8 days
and never saw this problem. I now have it set to 6 hours and still get
run out. I can't be 100% sure but I don't remember seeing that many
leases checked out by the RAS servers in the past. I could move to a
different series of IPs but I really dont have time to set up and test
that.

Any help would be appreciated.

Thanks,

REB

 

[Dusty Harper {MS}]

RRAS obtains leases in batches of 10. 4 RAS servers = 40 leases. If one of
those servers should run out of leases, it will get another batch of 10.
this means that potentially you could end up in a situation where only 1
server is taking calls, obtaining lots of leases and the other 3 are still
holding onto 10 leases each.

Have you added more devices to your network that helped deplete the DHCP
Addresses? This may have made the issue more noticeable.

 

[Ralph]

Actually with a headcount reduction there are 17 less computers on the
network. If I recall (and many of those braincells are too old to
recall) the RAS server used to use an IP addy then release it shortly
after the user disconnects. I don't have that many users accessing
the ras server. Some days there are no users connecting and still
they grab up IPs.

Thanks...

Gotta keep these few brain cells working

 

[Dusty Harper {MS}]

Like I stated, they will grab up 10 at a time. If a server has 20 leases
and only 5 people connect, the other set of 10 should be released back to
the DHCP server

 

[jmyner]

*I have had a RAS server set up on 2K server for several years.
Sometime around January I started running out of DHCP assigned
addresses. I traced it to the 4 RAS servers I have that are also
running 2K server. I have about 40 extra DHCP assinged addresses.
I
looked for a solution but just reduced the lease time to get around
it. No major changes have been made to the network except for MS
patches and updates. Can anyone explain why this recently starte
to
occur and if there is a fix? I used to have a lease time of 8 days
and never saw this problem. I now have it set to 6 hours and stil
get
run out. I can't be 100% sure but I don't remember seeing that many
leases checked out by the RAS servers in the past. I could move t
a
different series of IPs but I really dont have time to set up an
test
that.

Any help would be appreciated.

Thanks,

REB *

Why don't you define a static pool instead?

Open routing and remote access. Right click on the server name, selec
properties, click the IP TAB... and then define a static pool.

Good practice here is to use a portion of an existing DHCP addres
range and exclude those addresses in your DHCP server with a manua
exclusion range.

Doing this you've got RAS handing out IP addresses that are within you
existing DHCP specified range, as well as narrowing the field to
smaller number range that can tip you off later when troubleshooting
problem in the network. All without having to even touch the DHC
server to figure out who is from where.

Example...

Static range setup for 192.168.0.190-192.168.0.199

DHCP Range: 192.168.0.100-192.168.0.199
Exclusion: 192.168.0.190-192.168.199

If you don't have enough private addresses for this scheme with you
existing RAS servers and DHCP range, then in my opinion, it's time t
setup a seperate subnet for RAS clients or expand your existin
range/subnet.

Bye bye ugly RAS crap in the DHCP server. Bye bye dynamic registratio
problem


-
jmyne