10-01-2015 11:36 PM - edited 03-08-2019 02:01 AM
Hi Dears,
I have two 4500E Distribution switches for different VLAN ranges and different DHCP IP ranges.
One of them is working good after I configured IOS DHCP Server but the other is not working; it doesn't lease IP Addresses.
I have checked all configurations with the next and nothing different but IOS version and some Crypto PKI configurations.
Does DHCP Config has anything to do with these factors?
10-02-2015 12:29 AM
Can you post your dhcp config and show ip dhcp pool off the non working switch , are you connecting a laptop directly as a test
Did you debug dhcp detail to see if any packets were coming from the switch or use a wireshark ?
From experience sometimes re-applying the whole dhcp pool config can fix this , seen pools lock up before in ios and not give any addresses out
10-02-2015 12:45 AM
Hi Mark,
Thank you for the reply,
below is the show ip dhcp pool command result
Pool VLAN2-POOL :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 0
Excluded addresses : 254
Pending event : none
1 subnet is currently in the pool :
Current index IP address range Leased/Excluded/Total
0.0.0.0 10.0.2.1 - 10.0.2.254 0 / 254 / 254
and the dhcp config is as below:
interface Vlan2
ip address 10.0.2.2 255.255.255.0
ip helper-address 10.0.225.4 //this is Cisco works server
ip ospf network point-to-point
standby 226 ip 10.0.2.1
standby 226 timers 3 15
standby 226 priority 110
standby 226 authentication HSRP@XYZ
and the pool config is as below:
ip dhcp pool VLAN2-POOL
network 10.0.2.0 255.255.255.0
default-router 10.0.2.1
dns-server 10.0.225.44 10.0.225.22 213.55.96.166 4.2.2.2
option 43 hex 1f04.0a00.12fc
domain-name *****.com
shall i remove the dhcp pool configs and reinstall it again?
10-02-2015 12:55 AM
Hi just 1 thing why is there a helper address on the vlan when your trying to get your dhcp locally off the 4500, ip helper is only for clients when the dhcp server is not on the local subnet , your telling that subnet gets its dhcp off the helper but also try get it locally as there's a pool there , one may be over riding the other
If its not there for a specific reason fro cisco works can you remove that then reapply the pool again to the config and see if a client can pull an address
Have you any address exclusions set up as well in your config , the pool shows 254 addresses excluded
10-04-2015 10:51 PM
Hi Mark,
Thank you; The problem is i misconfigured the dhcp excluded-address range.
ip dhcp excluded-address 10.0.2.128 10.0.32.254 is the one I did but it should have been
ip dhcp excluded-address 10.0.2.128 10.0.2.254
10-05-2015 12:41 AM
ah good so your getting your client ips now from dhcp all working
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