Any way to do static dhcp on a 5510?

[Loxmyth]

My lab is behind an old ASA5510 box (yes, I know, legacy hardware, but it does give us the Vnet isolation and some firewall protection).

For testing purposes, I need to have one of the devices attached be assigned a stable address by DHCP. Unfortunately my understanding is that static DHCP bindings weren't supported in the latest official firmware for the 5510.

Is there an unofficial way to achieve this, short of dropping a newer router between the 5510 and the subnet and having it manage DHCP assignment?

Or is there an unofficial (Linux?) firewall  firmware alternative that would be worth trying?

Or is the 5510 so outdated that I should replace it entirely with a cheap moden router/firewall?

(Apologies if this is in the wrong group or I missed a prior answer, feel free to point me elsewhere or LMGTFY me.)


There's a claim at https://community.cisco.com/t5/networking-knowledge-base/dhcp-static-binding-on-cisco-ios/ta-p/3155731?attachment-id=90237 that this can be configured from the CLI, but I'm not sure I'm following what it's trying to tell me and I suspect it may not work on my old firmware.

[MHM Cisco World]

Static dhcp can not config 

Make your pool small for only two host ip, one ip for inside asa interface and other for user, this make asa always assing same ip to host 

[Loxmyth]

Hm. Single-address pool works if that's the only dhcp device on this vlan, which is not quite what I want.

Other router-like devices assume that addresses should be stable if possible -- their dhcp maintains the same mac to ip address mapping unless something else is already active and using that address. The 5510 apparently doesn't.

So replace the firewall or add a separate dhcp server either between or alongside? I presume the 5510 can be configured to refer DHCP requests elsewhere...?

[Loxmyth]

Actually, simply being able to extend the DHCP lease period to months (or a year) rather than a day would do it for me... But it looks like the maximum supported is about 12.5 days.

And the advanced DHCP options don't include option 51, which is the protocol-level set-lease-period option.

[MHM Cisco World]

I will check my note and update you soon 

[MHM Cisco World]

http://www.bigsoft.co.uk/blog/2013/02/02/configuring-a-permanant-dhcp-reservation-on-a-cisco-asa-pix

Check this link may be can help you to solve issue 

[Loxmyth]

Unfortunately, if you read down the discussion, it appears that either the person reporting this misled themselves or was using a newer version of the firmware after support for static DHCP was added (9.13; I'm on 9.8 or thereabouts and that's the last version the 5510 supports).

I'm sure supporting this was a near-trivial tweak to the firmware... but as far as I know a patch is not available.