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dhcp cylic allocation for particular vlan


we have extreme switch with following configuration

create vlan "vlan2001"
configure vlan vlan2001 tag 2001
configure vlan vlan2001 add ports 21-24 tagged
configure vlan vlan2001 add ports 10 untagged
configure vlan vlan2001 ipaddress 10.0.0.1 255.255.255.0
enable ipforwarding vlan vlan2001
configure vlan vlan2001 dhcp-address-range 10.0.0.3 - 10.0.0.100
configure vlan vlan2001 dhcp-options default-gateway 10.0.0.1
configure vlan vlan2001 dhcp-options dns-server 196.1.105.47
enable dhcp ports 21-24 vlan vlan2001
# show vlan2001 dhcp-config
DHCP Address Range : 10.0.0.3->10.0.0.100
Netlogin Lease Timer : Not configured (Default = 10 seconds)
DHCP Lease Timer : Not configured (Default = 7200 seconds)
Default Gateway : 10.0.0.1
Primary DNS Server : 196.1.105.47
Ports DHCP Enabled : 10, 21-24

Is it possible to tell switch to cycle through IP's .
say I have 20 devices . hey got 10.0.0.3-10.0.0.22
after two hours they should get 10.0.0.23-10.0.0.42
Next allocations will be 43-62 , 63-82 , (83-100 ,3,4) , 5-24 , ...
It should give new IP's till range gets exhausted .

Is that or something similiar possible ?

5 replies

Userlevel 1
Hi,
Not sure if you can get them to accept the next IP address in the range but you can adjust the lease.

configure vlan vlan2001 dhcp-lease-timer

I believe the defualt value is 7200 seconds, you can adjust from 0 - 4294967295

OR - maybe look into DHCP Bindings

Thanks
can switch assign random IP's when DHCP lease expires ? instead of going to lowest free in 10.0.0.3-10.0.0.100 range .
Userlevel 4
Typically clients will request the same IP they have at half (1/2) dhcp-lease-time. Normally DHCP servers will re-assign the client the same address (as requested by the client) since it matches the existing lease.
Userlevel 1
Can i ask why you need clients to be assigned different IP?
Actually , our systems gives acknowledgement when device changes its IP . I guess , i am asking something non-standard .

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