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Problem with DHCP

haji_akhundov
Level 1
Level 1

Hello everyone,

 

I'm typing in the following:

 

router(config)#ip dhcp excluded-address 172.16.2.0 172.16.15.255

 

and getting this:

 

% Address range contains an already reserved address.

 

 

How can I fix this issue?

 

Regards,

 

Haji

20 Replies 20

I think you know the answer to that. You would need to change the subnet mask to

255.255.252.0

for both the router and the pool, and you would need to move the lower range of the pool to

172.16.14.0



Sent from Cisco Technical Support iPad App

Jeff,

 

I can't do that. Can't change the subnet. I have other devices in the range that use static addressing.

 

I did resolve the problem for the moment.

 

I did the folowing:

 

ip dhcp excluded-address 172.16.2.0 172.16.5.0

ip dhcp excluded-address 172.16.6.0 172.16.15.255

 

and it works fine.

 

The problem was that I had several of these for the

172.16.5.0

network:

 

ip dhcp pool Samsung

   host 172.16.5.41 255.255.240.0

   client-identifier 0188.308a.xxxx.xx

   default-router 172.16.15.254

   dns-server 172.16.2.1 172.16.2.2

   netbios-node-type h-node

   lease 10

 

that's why the exclusion didn't work. (Although it did before. strange.)

 

Thanks for the input!

blau,

 

i've tried doing what you suggested:

 

it gives me the following error:

 

% Specified address out of pool's subnet range

 

when i input:

 

address range

172.16.0.0 172.16.1.255

 

Thanks.

blau,

 

i changed this and now it works:

 

address range

172.16.0.1 172.16.1.255

 

But look, I still have this problem:

 

router#show ip dhcp pool a-pool




Pool a-pool :

Utilization mark (high/low)    : 100 / 0

Subnet size (first/next)       : 0 / 0

Total addresses                : 4094

Leased addresses               : 0

Pending event                  : none

1 subnet is currently in the pool :

Current index        IP address range                    Leased addresses

172.16.5.19          172.16.0.1       - 172.16.15.254     0                   

No relay targets associated with

class LIMIT-DHCP-SUBNET

 

What should I do to reset this?

Jeff,

 

Sounds like a nice idea.

 

But can we have the two different?

 

ip dhcp pool lsr-pool

   network 172.16.0.0 255.255.240.0

   default-router 172.16.15.254

.




interface GigabitEthernet0/1.2

ip address 172.16.15.254 255.255.240.0

 

Regards

if you have static entries, then that it is was is causing the error

solution:

conf t

no serv dhcp

add the exclusion, then activate again:

serv dhcp
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