DHCP reservation doesn't work anymore with Leopard

If your DHCP server hands out addresses based on the client's hardware address, then the OS is irrelevant.

Check the settings on your DHCP server.

Is the reserved IP address outside of the auto assigned range? If it isn't, someone else may already have been assigned the reserved address and it isn't available when your MAC requests it. Most DHCP servers will assign a reserved IP address if it's available. If it's in the automatic assign pool, the reservation will not prevent it being assigned to someone else.

I have the same problem. I don't think its my router (NETGEAR) since other machines on the network have no issues.

Has anyone come up with a resolution to this? The DHCP reservations are working on other computers in the network except mine (a MacBook with an airport connection to the router).

Well, I figured out my own issue (a major duh moment for me, I've seen too many MAC addresses today). I had the router reserving the IP address for my ethernet's MAC address and NOT the wireless MAC address. Once, I sorted that out, it worked.

I have been struggling with similar problems with the Netgear WGR614v6.

Before Leopard I ran this router without any incidents using it to reserve addresses for seven devices (Macs, a DVR, a Wii) without problems. Each machine was always assigned the address in the reservation table (LAN IP Setup on Netgear) based on its MAC address.

When we upgraded to Mac OS 10.5 I began to have difficulties with iChat and tried a different router. Those iChat issues turned out to be non-router-related, so after a couple months I put the Netgear back online since I like it much more than the alternative I was using.

Now that it is back I've found the Netgear no longer assigns the Macs their reserved addresses. I've tried upgrading and downgrading firmware (now running V2.0.13_1.0.13NA which worked for me before all this started), reentering all settings from scratch a number of times, nothing seems to work. UPnP is off.

I can and do assign a manual IP addresses to one of our desktop machines so that I can use port forwarding to that machine. But this is not a convenient solution for a laptop which moves regularly to other DHCP environments.

It does appear that something in Leopard has broken the Mac's ability to get the proper address from the DHCP server running on the Netgear box. That puzzles me since all the Netgear box needs to know is the MAC address of the requestor, right? Is the Macintosh no longer sharing its proper MAC address when it tries to get an IP address after being asleep?

Anyway, if anyone resolves this problem, I'd love to hear how. We are getting a bit tired of "your IP address is already in use by another computer" messages at my house!

...Eric

Though I normally use 'normal' DHCP addresses for my wireless clients, this got me curious.

My Macbook is running 10.5.1

So, I configured my OpenWRT WRT54 router with a static IP for my Macbook's Airport Mac address, different from the one it's been getting dynamically for months, and did DHCP RENEW on my Macbook. My Macbook instantly reconfigured with the new address, and everything continued to work just fine.

For those having problems, a tcpdump log of the DHCP transaction instigated by a RENEW would probably be helpful.

Yes, I'm having the same problem....MAC 10.5.2 isn't handling DHCP address reservation properly with my netgear router.......but it works fine with my windows machine.

BTW, I am using it with Netgear WGR614v5

I've been having the same problem with Leopard and the WGR614 v6. I tried this experiment today. Maybe someone can interpret these results and figure out what the problem is.

1. I reset the router and reinstalled most updated firmware (V2.0.19_1.0.19NA).
2. I limited the DHCP range to 192.168.1.2-192.168.1.7 (One address for each of the 4 ports plus one wireless)
3. Set the reserved IPs for the hardwired PC and Mac to 192.168.1.2 and 192.168.1.3 respectively.
4. Took everything offline from the modem to the boxes and powered everything down.
5. Brought the modem back up, then the router, then the boxes.

Here is the result:

The PC on the network took the proper reserved address and after asking it to renew, it was provided the same address: 192.168.1.2. The Mac initially took the correct reserved address: 192.168.1.3. However, when asked to renew, the Mac was assigned 192.168.1.4. A second renewal provided 192.168.1.5. This continued until I hit 192.168.1.7 (the final address in the DHCP range). On the next renew, I expected it to recycle back to 192.168.1.3, however it did not. At that point it failed to return an address no matter how many times I renewed. I had to log into the router and re-reserve the IP to get the Mac a working IP.

Now, before every network guru jumps all over me for trying to reserve addresses WITHIN the DHCP range, we have already confirmed this is correct practice for the Netgear product on their boards. Any attempt to reserve an address OUTSIDE the DHCP range results in an error message being returned by the router strictly forbidding that practice. The address I have reserved for the Mac is NOT being assigned anywhere else. So, the address is available in the pool, but the router appears not to recognize the Mac (it uses MAC address) as having a reserved address when it asks for one. Also, having the Mac manually take an address from the router doesn't work either in my experience. When trying a manual assignment, network diagnostics show the connection failing at "Internet level." That is, I get the first 3 "lights" green down to ISP. However, the last two "lights" are still red.

Not sure that this will help, but it is clear that the WGR614 (name your flavor) is not working and playing well with Leopard from a reserved IP standpoint.

I replaced my router with a WGR614v9 and SOLVED THE PROBLEM. My new router is v9 of the hardware (not v6) and running firmware V1.0.9_1.0.1NA. I did this after calling Netgear and being told they could fix the problem by replacing my WGR614v6 with a new router, but I'd have to pay shipping. Well, shipping was slow and buying a new router cost only a bit more ($40 at Radio Shack). I installed the new router on Friday, set it up exactly as I had set up the v6, and have had not a single problem since. Every Mac now gets its reserved address just fine.

So, for me, this points at Netgear as the problem. Something in their newer router works better than it worked in their older one. Whatever that is does not seem to be solved by the most recent firmware for the v6 version of the router.

Not that it helps but I am having a very similar issue. I also have a Netgear "WGR614 v7" I have been using reservation on a number of other devices and it works fine but not with my Mac mini. I am sure I will just give it a static address but its odd that this issue seems to be some incompatibility with the Mac ethernet hardware or OSX. Maybe its not reporting its mac address the same every time?

All I know, is its not working for me either.

Still good to get feedback. From what I can gather from here and the Netgear forums, there is a toxic interaction with 10.5.2 and the WGR614 V1-8. There have been some reports of folks being OK with 10.5.1 and the problem does not exist in v9 and above routers. In fact, if you have purchased your router recently enough for Netgear to feel obligated to help, they will just send you a v9, which solves the problems. Curious little problem though. Considering the v9 doesn't have this problem and it didn't start with pre v9s until 10.5.2, its hard to say exactly who broke things or better yet, why Netgear can't find a firmware fix for pre v9 routers.

Message was edited by: Adam Salerno