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Renew DHCP Lease
- Thread starter DianeK
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Connected as follows:
1. Cable to Cisco router
2. Time Capsule ethernet connected to Cisco
3. Macbook Pro and iMac access the internet via wifi to either the Cisco network or the Time Capsule network. My iMac is in a different room than the Cisco and Time Capsule so I find the Time Capsule to be a more reliable network access. My husband's Macbook is in the same room as the Cisco and Time Capsule so both of those are reliable for him.
4.
Tv in basement is ethernet connected to Cisco.(long cable runs through a hole in floor)Sorry, a bit long winded but figured you should have the whole story. Since my network access using the Cisco is not reliable we were wondering if we should renew the DHCP lease.
As an aside we cannot see each other in AirDrop.
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The DHCP for your local network (in your house) is being done by your Cisco as a router (I presume). However, the Time Capsule also has the ability to be a router and can also give out IP addresses. To avoid a conflict, the TC needs to be in Bridge Mode - have you checked this ? Does the Cisco also do WiFi ?
Normally IP problems are caused by something changing on your local net. Have you added something or moved some connections around ? If it was all working before, then try turning everything off and then on again in the order :
1. Cisco
2. Time Capsule
3. iMac
4. MacBook
5. Apple TV
Wait a min or between each one to ensure the boot process completes.
Does all your other stuff work apart from WiFi ? What specifically is the problem ?
PS. Unless your DHCP lease from the Cisco is really long (say a month), then the IP addresses should automatically renew in a short time. Have you checked the setting in the Cisco ?
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Thanks for your input.
The main problem is that my iMac's connection to the wi-fi is unstable since upgrading to ML from SL. Of the two access points (Cisco, TC) my iMac has steadier connection via the Time Capsule, so if we were going to bridge anything, it would be the Cisco. Wi-fi was very stable with SL and the software is the only thing that has changed (unless there is some extra traffic in the neighbourhood that we don't know about).
And no, not all else is well with my iMac since the ML upgrade although the wi-fi issue is the most aggravating - cannot use AirDrop, dropped or slow wi-fi connection. The other thing my iMac is doing occasionally is after waking from display sleep (especially a long sleep), it loses the desktop....all I have is the ribbon up top and the rest is white - no icons, no dock. Luckily, the ribbon always appears on wake-up so I can reboot and get my desktop back. And sometimes only chunks of the desktop are missing and replaced with white - very weird.
The main problem is that my iMac's connection to the wi-fi is unstable since upgrading to ML from SL. Of the two access points (Cisco, TC) my iMac has steadier connection via the Time Capsule, so if we were going to bridge anything, it would be the Cisco. Wi-fi was very stable with SL and the software is the only thing that has changed (unless there is some extra traffic in the neighbourhood that we don't know about).
And no, not all else is well with my iMac since the ML upgrade although the wi-fi issue is the most aggravating - cannot use AirDrop, dropped or slow wi-fi connection. The other thing my iMac is doing occasionally is after waking from display sleep (especially a long sleep), it loses the desktop....all I have is the ribbon up top and the rest is white - no icons, no dock. Luckily, the ribbon always appears on wake-up so I can reboot and get my desktop back. And sometimes only chunks of the desktop are missing and replaced with white - very weird.
I would recommend making DHCP reservations in your Time Capsule router. Make your Cisco bridge mode and then install your ISP information in the Time Capsule.
Under the settings for DHCP reservations, enter the MAC address of each device in there and it will then assign that address to each device. I personally put all my computers in the .10 range, my iPhones, iPods, iPads, in the the .20 range. My other items like DVR, thermostat, SlingBox get assigned in the .30 and .40 range. This ensures that nothing is trying to use the same IP.
Once you have done that, if you continue to have problems, change the channel on the wireless network in the settings of the Time Capsule (Airport Utility) to a dedicated channel. Try a few different ones to see if that is the problem.
Under the settings for DHCP reservations, enter the MAC address of each device in there and it will then assign that address to each device. I personally put all my computers in the .10 range, my iPhones, iPods, iPads, in the the .20 range. My other items like DVR, thermostat, SlingBox get assigned in the .30 and .40 range. This ensures that nothing is trying to use the same IP.
Once you have done that, if you continue to have problems, change the channel on the wireless network in the settings of the Time Capsule (Airport Utility) to a dedicated channel. Try a few different ones to see if that is the problem.
Can I suggest then that you use the Cisco only as a Modem. Is that possible ?
See if you can turn OFF the Cisco router functions and the Cisco WiFi functions.
Then you can setup the TC as the router and as the WiFi access point. You will also have to run all LAN connections through the TC. Maybe you will need an additional small Gigabit switch if there are more than 3 required ($30 or so).
Can you try running a LAN connection from the iMac to the TC and using that for a while to see if the iMac problems go away ?
If you do all this, then make sure you reboot everything as I outlined.
See if you can turn OFF the Cisco router functions and the Cisco WiFi functions.
Then you can setup the TC as the router and as the WiFi access point. You will also have to run all LAN connections through the TC. Maybe you will need an additional small Gigabit switch if there are more than 3 required ($30 or so).
Can you try running a LAN connection from the iMac to the TC and using that for a while to see if the iMac problems go away ?
If you do all this, then make sure you reboot everything as I outlined.
"drsox" and "kycophpd": thank you very much for all your suggestions. My husband is leaving on a business trip early tomorrow morning taking his MBP and I am reluctant to muck around with our wireless system in his absence as I am just not all that comfortable with the computer universe 
. When he returns, we will try what you have suggested, i.e. bridging the Cisco and using TC as the router and making the appropriate DHCP reservations.
Question for "drsox" regarding creating an ethernet LAN connection from my iMac and the TC...is this to see if my iMac is having internet issues in general versus my assumption of wi-fi issue? My other option with my husband gone, is to move my iMac into his office so it is sitting next to the Cisco and TC and see if my wi-fi settles down (as his wi-fi seems stable). However, I won't be able to test out AirDrop which is where my problems with wi-fi really manifests itself.
Also, anyone have any ideas about the weird desktop issue I described in my previous post?
Diane
. When he returns, we will try what you have suggested, i.e. bridging the Cisco and using TC as the router and making the appropriate DHCP reservations.Question for "drsox" regarding creating an ethernet LAN connection from my iMac and the TC...is this to see if my iMac is having internet issues in general versus my assumption of wi-fi issue? My other option with my husband gone, is to move my iMac into his office so it is sitting next to the Cisco and TC and see if my wi-fi settles down (as his wi-fi seems stable). However, I won't be able to test out AirDrop which is where my problems with wi-fi really manifests itself.
Also, anyone have any ideas about the weird desktop issue I described in my previous post?
Diane
Before my husband packed up his computer for his trip, I moved my iMac to the same desk that the MBP, Cisco, and Time Capsule sit on. No improvement in connectivity performance. No AirDrop.
Diane
Before my husband packed up his computer for his trip, I moved my iMac to the same desk that the MBP, Cisco, and Time Capsule sit on. No improvement in connectivity performance. No AirDrop.
Diane
Can we go back to the beginning.
Is your iMac still next to the Time Capsule ?
Can you try connecting by a cable from the iMac to the TC ? Does that work OK ? Make sure you restart the iMac.
Now try connecting from the iMac to the Cisco. Does that work OK ? Make sure you restart the iMac.
Does the Apple TV work OK ?
Step 2
Are both the Cisco and the TC operating with WiFi ?
Unplug the LAN cable from the iMac and restart it. Does it connect via WiFi ?
Can you check which unit the iMac is connected to ? Do you know how to do this ?
Sorry, last night I should have also posted that we did connect the iMac to the TC via ethernet to see if there would be improved performance with a direct connection. Websites did not load any faster and there was the same occasional lag times when reloading pages or playing games (hate to admit that as a 60-something woman I do play computer games, lol). So my feeling is that internet performance didn't really improve with ethernet connection.
We didn't think to try direct connection to the Cisco though, oops. And my husband now has that ethernet cable with him on his trip.
Yes, both the Cisco and TC have wifi operational - we haven't bridged the Cisco yet. I have the TC set at the top of the list of my preferred networks because its wifi seemed to provide a more stable connection when I was in my home-office so that's the one it preferentially connects to. Now that I am in my husband's home-office, the Cisco and TC wifi seem to operate equally well.
The ATV seems to work fine - so far we have used it for Netflix, YouTube however I would expect that to work fine because of its ethernet connection to the Cisco. I did stream a Lightroom slideshow from my iMac via AirPlay mirroring the other day and that worked fine. What I haven't yet tried is streaming a movie or a concert via AirPlay mirroring from my iMac (as I think that may be a bit more taxing on the wifi connection) and will likely try that this evening.
Well, interestingly, when I went to preview this post, I needed to re-login so does this mean that while I was typing my connection to this forum was dropped?
I really do appreciate all the help you are providing.
Hey, just another thought. We can "see" (as in they are listed when I click on the wifi icon in the upper right corner) two neighbors' networks. This is not new, have been able to see them for a couple of years (when I still had Snow Leopard). But I was wondering if there is something different with Mountain Lion wifi drivers that causes my computer to go hunting all the time for a better signal and that hunt includes "checking out" the neighbors' wifi and if this could be causing the lags and general slowness of my connection? Is there a way to tell the computer to ignore these networks?
I'll tell you what I think are the possibilities.
1. The Cisco WiFi is getting in the way of the TC WiFi. You need one or the other. I suggest disabling the Cisco WiFi.
2. Your upgrade from SL to ML didn't go completely well and you may need to reinstall ML. Presumably your iMac is new enough that it wouldn't have a problem with ML.
Also
3. Maybe the two routers are also fighting each other and (IMO) you should disable the Cisco's routing functions.
Your testing the ATV via LAN seems to show that the Cisco is working OK, but IMO you will be better off connecting all LAN stuff to the TC.
Re other networks, are the other networks of equal strength to your own networks ? If so, then it might cause a lag, but it might also be caused by having both the Cisco's WiFi and the TC's WiFi in your Preferred Networks list. You are already telling the iMac to ignore other networks by only listing two in this list, but it will still show all possible available.
Lastly, are you on 2.4Ghz or 5Ghz. If possible, see if you can go 5Ghz (much better in my experience). I have to deal with an iPhone 4S otherwise I would be 100% 5Ghz.
1. The Cisco WiFi is getting in the way of the TC WiFi. You need one or the other. I suggest disabling the Cisco WiFi.
2. Your upgrade from SL to ML didn't go completely well and you may need to reinstall ML. Presumably your iMac is new enough that it wouldn't have a problem with ML.
Also
3. Maybe the two routers are also fighting each other and (IMO) you should disable the Cisco's routing functions.
Your testing the ATV via LAN seems to show that the Cisco is working OK, but IMO you will be better off connecting all LAN stuff to the TC.
Re other networks, are the other networks of equal strength to your own networks ? If so, then it might cause a lag, but it might also be caused by having both the Cisco's WiFi and the TC's WiFi in your Preferred Networks list. You are already telling the iMac to ignore other networks by only listing two in this list, but it will still show all possible available.
Lastly, are you on 2.4Ghz or 5Ghz. If possible, see if you can go 5Ghz (much better in my experience). I have to deal with an iPhone 4S otherwise I would be 100% 5Ghz.
Thank you.
I agree we should try using the Cisco as a modem only and for this I will wait until hubby gets home. Go ahead, call me a wussy, lol
In the back of my mind has been lurking the dark cloud of a possible re-install of ML in my future.
Yes, the network right next door is as strong as both of ours.
Re: Ghz
We have an iPhone4 and iPhone3Gs so I assume that would also preclude us from using 5Ghz? But out of curiosity, how do I check what GHz we are using?
I went to System Report for wi-fi but didn't see anything there. What I did see there is that our Cisco and TC are 802.11n, Cisco Channel 6, TC Channel 1. The neighbour who has the strong signal is on 802.11g but also on Channel 6, the same as our Cisco. I'm assuming they probably have the same ISP and Channel 6 is the preferred one for our neighbourhood?
BTW, what's the difference between WPA and WPA2Personal? The neighbour is WEP.
And another thing...The TC network appears in two places 1. Current Network Information and 2. Other Local Wi-Fi Networks with the last two characters of BSSID different. Also, under the Current info the channel is both 149 and 1 whereas under the Other info the channel is only 1. Also Signal/Noise is different between the Current info and the Other info.
I agree we should try using the Cisco as a modem only and for this I will wait until hubby gets home. Go ahead, call me a wussy, lol
In the back of my mind has been lurking the dark cloud of a possible re-install of ML in my future.
Yes, the network right next door is as strong as both of ours.
Re: Ghz
We have an iPhone4 and iPhone3Gs so I assume that would also preclude us from using 5Ghz? But out of curiosity, how do I check what GHz we are using?
I went to System Report for wi-fi but didn't see anything there. What I did see there is that our Cisco and TC are 802.11n, Cisco Channel 6, TC Channel 1. The neighbour who has the strong signal is on 802.11g but also on Channel 6, the same as our Cisco. I'm assuming they probably have the same ISP and Channel 6 is the preferred one for our neighbourhood?
BTW, what's the difference between WPA and WPA2Personal? The neighbour is WEP.
And another thing...The TC network appears in two places 1. Current Network Information and 2. Other Local Wi-Fi Networks with the last two characters of BSSID different. Also, under the Current info the channel is both 149 and 1 whereas under the Other info the channel is only 1. Also Signal/Noise is different between the Current info and the Other info.
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"But I was wondering if there is something different with Mountain Lion wifi drivers that causes my computer to go hunting all the time for a better signal and that hunt includes "checking out" the neighbors' wifi and if this could be causing the lags and general slowness of my connection?"
This may or may not help.
You can download a free utility called "iStumbler". When you run it, it shows you all the nearby wireless networks, and what channels they're using.
You want to pay attention to which channels (other than your own) are in use. If you and a nearby wireless user are using the _same channels_ there could be some conflicts that might result in a slowdown.
I believe you can set up your own wireless network to specify which channels will be used.
You want to pick channels that _are not_ being used by other nearby networks, and use those channels for your own wireless.
Another unrelated issue:
As others have mentioned, if you have both the Cisco and the TC set up as routers, you have "double NAT" (network address translation) going on. This could be a problem.
You should configure the Cisco to be in "dumb mode" (modem only with the router capabilities turned off), and let the TC do the routing.
(aside: this post probably duplicates what others have said already)
This may or may not help.
You can download a free utility called "iStumbler". When you run it, it shows you all the nearby wireless networks, and what channels they're using.
You want to pay attention to which channels (other than your own) are in use. If you and a nearby wireless user are using the _same channels_ there could be some conflicts that might result in a slowdown.
I believe you can set up your own wireless network to specify which channels will be used.
You want to pick channels that _are not_ being used by other nearby networks, and use those channels for your own wireless.
Another unrelated issue:
As others have mentioned, if you have both the Cisco and the TC set up as routers, you have "double NAT" (network address translation) going on. This could be a problem.
You should configure the Cisco to be in "dumb mode" (modem only with the router capabilities turned off), and let the TC do the routing.
(aside: this post probably duplicates what others have said already)
Thank you.
I agree we should try using the Cisco as a modem only and for this I will wait until hubby gets home. Go ahead, call me a wussy, lol
In the back of my mind has been lurking the dark cloud of a possible re-install of ML in my future.
Yes, the network right next door is as strong as both of ours.
Re: Ghz
We have an iPhone4 and iPhone3Gs so I assume that would also preclude us from using 5Ghz? But out of curiosity, how do I check what GHz we are using?
I went to System Report for wi-fi but didn't see anything there. What I did see there is that our Cisco and TC are 802.11n, Cisco Channel 6, TC Channel 1. The neighbour who has the strong signal is on 802.11g but also on Channel 6, the same as our Cisco. I'm assuming they probably have the same ISP and Channel 6 is the preferred one for our neighbourhood?
BTW, what's the difference between WPA and WPA2Personal? The neighbour is WEP.
And another thing...The TC network appears in two places 1. Current Network Information and 2. Other Local Wi-Fi Networks with the last two characters of BSSID different. Also, under the Current info the channel is both 149 and 1 whereas under the Other info the channel is only 1. Also Signal/Noise is different between the Current info and the Other info.
1. To check what you are using look at the following :
On your iMac do Alt left click on the Wireless icon in the top right part of your screen (has 3 curved segments and a dot - looks a bit like an ice cream cone). It will reveal what you are connected as (mine says Channel 36 (5Ghz) plus some other stuff). You will also see the SSID name in System Preferences>Network>Wi-Fi>Network Name.
On your IOS units look at Settings>Wi-Fi.
2. Looks like your neighbours's WiFi is interfering with your Cisco. All your WiFi is on 2.4Ghz. There are only 3 frequencies that don't overlap at 2.4Ghz : 1,6,11. I suggest changing the Cisco to Channel 11. There should be a menu select somewhere in the Cisco setup.
3. WEP is Wireless Equivalent Protocol and is the easiest to break into. WPA is better and WPA2-Personal is best. If it is a potential issue for you then go to WPA2 (all mine are on WPA2) and use a strong password with a mixture of characters e.g. (not mine) Qn?9h%1dT* etc for at least 10 characters. I have this for all my On-Line financial logins as well as the iTunes password and WiFi stuff. (To remember it all I have another list file with an ever stronger password that I CAN remember ! - or use something like 1Password)
For more info than you need, look at this : http://en.wikipedia.org/wiki/Wi-Fi_Protected_Access !
4. Your TC is transmitting on 5Ghz (Channel 149) and 2.4Ghz (Channel 1) simultaneously.
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Thank you.
Option+click wifi revealed channel 149 5Ghz for the TC
Re: setting Cisco to channel 11 - I'm going to call our ISP and have them walk me through it on the phone - not confident enough to do this on my own. It will really only be as an experiment for just this week if we are going to bridge the Cisco next week when hubby returns. But in the meantime if I change the channel and move my computer back to my room away from the Cisco and TC and choose the Cisco network it should show if the neighbour also using channel 6 has been contributing to the problem if the Cisco suddenly provides more consistent connectivity.
Any thoughts on the TC showing in both Current and Other info categories in the System Report window? Or is it showing up under Other because it is "current"ly transmitting in 5Ghz and the 2.4Ghz channel is the "other"?
And lastly, I think AirDrop not working is something else entirely (even though it is a wi-fi function) and is probably going to require a reinstall of ML - major anxiety here at the thought of that
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Going into "About this Mac" --> System Report gave me this information.
And yes, your other information confirms what I have already be advised.
Thank you very much for chiming in.
Thank you.
Option+click wifi revealed channel 149 5Ghz for the TC
Re: setting Cisco to channel 11 - I'm going to call our ISP and have them walk me through it on the phone - not confident enough to do this on my own. It will really only be as an experiment for just this week if we are going to bridge the Cisco next week when hubby returns. But in the meantime if I change the channel and move my computer back to my room away from the Cisco and TC and choose the Cisco network it should show if the neighbour also using channel 6 has been contributing to the problem if the Cisco suddenly provides more consistent connectivity.
Any thoughts on the TC showing in both Current and Other info categories in the System Report window? Or is it showing up under Other because it is "current"ly transmitting in 5Ghz and the 2.4Ghz channel is the "other"?
And lastly, I think AirDrop not working is something else entirely (even though it is a wi-fi function) and is probably going to require a reinstall of ML - major anxiety here at the thought of that
----------
Going into "About this Mac" --> System Report gave me this information.
And yes, your other information confirms what I have already be advised.
Thank you very much for chiming in.
Yes, my AExtreme shows up twice in any WiFi listings - once for each band. I have different SSID names for each band so that I can chose which is preferred for connection.
Yes, you might find that the Cisco now performs OK.
Reinstalling ML is no big deal other than downloading the stuff again. If you are brave, you might try creating a USB installer (google ML USB installer), but I've been unsuccessful so far (operator error).
Have fun tinkering.
Thanks for confirming that double entry for the TC is normal.
I did copy the ML installer onto a bootable USB before installing it but quite frankly, if it needs a clean install I will take it to the "hospital". It is still under AppleCare and the AirDrop issue is an open case with Apple Support.
If changing the Cisco channel and/or bridging the Cisco resolves things, I will post back here just to bring closure to this thread. And if Apple Support resolves the AirDrop issue I will also post that info here for completeness.
Thank you so very much for the time you have dedicated to this!
Cheers,
Diane
"Glad to help, Ma'am" - Doffs Hat
"All part of the service" - Turns and rides into the sunset