Have to constantly renew DHCP lease

I'm no network guru either but by a very painful 3-day process of elimination (when I should have been doing DIY projects! - wife not happy), I found a solution that works for me so far. Although, there is one test to do - whether it will last more than 24 hours!

I had - iPad, iPhone, iMac, wireless printer. My iMac uses ethernet to a small netgear switching router which is connected to my powerline ethernet. The powerline ethernet goes downstairs to another powerline ethernet that my Airport Extreme is wired to. My Airport Extreme is a wireless extension of my Airport Express. My Airport Express is linked via ethernet to my O2 wireless router.

I know that's complicated but I'm in an old Victorian house with thick walls and lots of steel, iron and plaster, it's complicated.

I eventually tracked down the problem to definitely being between the router and my iMac. Every time I turned on my iMac or shutdown, I'd loose internet connection on my iPhone and iPad - they can see the local network but not the internet. So the router isn't letting them 'leave the building' to go find the internet. Maddening.

It was also just turning off the internet conneciton on my iPhone and iPad randomly when the iMac was on all day - not just on boot up and shutdown.

They'd only work if I turned on and off my router every 15 mins or so. Drove me crazy.

So it had to be an IP problem. It's the only thing I could think of. I switched my iPhone and iPad to just connecting to the O2 router - still nothing. So it wasn't my Airport network causing the issue.

My iMac was connected the internet every time.

So - it's definitely to do with the DHCP lease.

I changed the IP address Using DHCP iwth manual address. But then lost all internet connection not only on my iphone and ipad but now my iMac too. Silly me - because of course, you have to tell your router that you are changing it to a static address too.

I also changed IPv6 to local link only in case that was causing issues (I can't think why it would but it was some positive action I could take). And I changed the location to Automatic in case that was having an issue too. Again, can't think why it would but anything at this stage was a possibility.

So far, so good. I'll keep you posted. But I'm so keen to solve this maddening problem I'll stay up all night if I have to. I'm also so maddened by it, I really want the world to know when I have a solution so they don't have to go through the same thing!

Apple - just tell every one a fix - Please!!!!!

Reggie Carey wrote:

I see lots of complaints by lots of customers but I don't see anyone from Apple responding with a solution.

And you never will. They are never allowed to openly respond here, it's for users only. There is no guarantee that anybody from Apple will even read your posting here. That's not what this forum is for.

If you need to communicate with Apple go to their Feedback page. If you are unable to resolve the problems with your MBP with our help then you need to take it to the Genius bar or a certified Apple repair facility.

I've struggled with this issue from time-to-time until I flushed the DNS cache.

Try

1. Open the Network Status menu: Apple menu > System Preferences > Network.
2. Select the active connectionfrom the Network Status menu and click Advanced.
3. Click Renew DHCP Lease. This process may take a few minutes.
4. Close the Network window.
5. Flush the DNS cache by opening Terminal. (Go > Utilities > Terminal).
6. Type in the following:
   dscacheutil -flushcache

That, hopefully, should do it.

It could be hard to say what's causing the problem since you don't know exactly when it started (before or after the upgrade).

Do you have any other computers or devices that work when the computer can't connect?

What modem and router type or you using?

If the firmware updated on those?

You could create a new user account to test and see if the connection issue persists.

I would definitely check the firmware on the router for upgrades.

If you think it happened after upgrading to 10.7.3, you might try downloading the ComboUpdate from the Apple site and reapply over the existing OS if the new user account fails the test.

You can also add the DNS address to the network settings under the advacned tab. The address you put would depend on where the DNS is obtained from. If from the router, then you would put the router address address here since the router itself would contain the outside DNS settings. You can see that by looking at the network settings for the router and DNS address. Most DNS manuel input for the outside servers would be put into the router settings, not in the computer network settings. Also, make sure the router setting in the network setting is not an address being distributed by the DHCP server in the router settings. Also lease settings should be set in the router and should not have to be renewed by you manually.

I'm having the exact same issue in both wireless and with ethernet. Its actually more prevelant with the wired connection. It has gotten to the point that I must manually refresh my DHCP lease before each time I access a new web page or before I check my email. I have replaced my router and modem and the problem has persisted. My other devices on the network don't share this affliction.

MacBook Pro 15" 2.2GHZ i7, 8GB 1333MHz DDR3 OS 10.7.3

i used to have problems with my wifi to, it used to drop out all the time on my apple tv ps3 and mac on snow leopard but i found a fix and that was to access my router settings by typing my ip address into safari (where the web page address normally goes) and once in my router setting changing the channel number of my wi fi from auto to a random number between 1 and 15. I found if there are other wifi routers in the same area as u then sometimes they clash on what channel they broadcast on, try each number between 1 and 15 untill u have a stable connection, dont know if this will help but ive had zero connection problems since

I have the same problem. I have to constantly renew the DCHP lease. Web access will freeze and once I renew the DCHP lease it starts again. I also use a MacBook Pro running the latest ver. Lion. This problem sems to have started within the past 2 weeks. I use this same MacBook Pro at my work and I do not have the problem there. So, for me anyway, it is obviously caused by my home setup. I use a UBEE modem and Linksys switch to distribute Internet at home.

I have the same issue that every 10-15min my connection freezes-drops. Gotta renew leased DHCP to get it working again, only to have to do everything again after other 10-15minutes- Only thing it's i'm on SnowLeopard 10.6.8. I've been experiencing this really annoying problem for 2-3 weeks now. Before everything worked flawlessly and it's not an ISP related problem, as my flatmate using crappy win 8 doesn't have any problems or whatsoever.

I have the exact same problem with both wi-fi and ethernet connections and it's driving me crazy!

It only started after I upgraded from Snow Leopard to Lion. It is really very frustrating; as a web designer, I now have to spend much of my day clicking on the "Renew DHCP Lease" button in the TCP/IP pane in the Network control panel.

My iPhone has no trouble at all accessing the same wi-fi network. My old G4 tower Mac running Leopard has no trouble either. It's just my intel iMac with 10.7.4.

I can usually figure out what's causing this sort of glitch but so far this has me stumped. :-/

Anyone get ony other thoughts or ideas on any differences in Lion's networking architecture that might be the cause of this?

one thing ive noticed coz im having a prob with safari now sometimes it dont load and renew DHCP lease makes it go again is i have itunes open constantly on my mac and have got itune match running for my music im wondering if this could be something to do with it as nvr had the prob before i got itunes match?

Same here. I'm running a Mac Pro tower with both wired and wi-fi connections and I have to renew my DHCP lease every 15 minutes or so. I've tried manual addresses, setting a 10 second ping to keep connections alive, etc.

Up to date on software and this issue did not develop for me either till 10.7.4. Other hardware on the same network does not have this problem.

igiveuphelp wrote:

Same here. I'm running a Mac Pro tower with both wired and wi-fi connections and I have to renew my DHCP lease every 15 minutes or so. I've tried manual addresses, setting a 10 second ping to keep connections alive, etc.

Up to date on software and this issue did not develop for me either till 10.7.4. Other hardware on the same network does not have this problem.

One new thing that many people are finding is network difficulties after Worldwide IPv6 day on June 6. Some find that disabling IPv6 on their Mac improves the situation while others have found exactly the opposite. Most ISP's have not implemented it yet, so that's a major part of the problem, so you might want to check with yours to see if they have yet. If not, you are probably better off making sure your entire network has it set to either "Link-local Only" or "Off".

To disable on your Mac Select  ▹ System Preferences ▹ Network ▹ Airport ▹ Advanced ▹ TCP/IP ▹ Configure IPv6: Off.

Click "OK" and then the "Apply" buttons.

I have had the same problem on only my 17" Macbook pro for a month now on both ethernet and wireless. Finally now my airport won't even turn on so I imagined its dead. So I bought a Panda Wireles USB network Adapter.

Now oncw again I can get on wirelessly but I still need to renew the DHCP lease every 30 seconds or so.

I tried you suggestion MadMac, but alas it did not work for me. I have a feeling that going to a Mac Genius bor won't help either.