Home LAN: Ethernet over Power Networking problem

[rkv]

I am having an ethernet connectivity problem, where my iMac and Mac Book Pro cannot connect to my home lan when I plug the ethernet cable directly into their ethernet ports. However, if I plug the ethernet cable into an apple usb to ethernet adaptor and connect via the iMac or MBP USB port, every thing works fine. My suspicion is that something with the DHCP handshake is timing out when connected via the computers ethernet adapter as opposed to using apples USB to ethernet adaptor.

I am trying to use Devolo dLan powerline adaptors to run an ethernet connection to a room where I have poor wifi signal. Ideally I would like to locate an airport express and an iMac in the room. I have both Devolo dLan 500 and dLan 200 adaptors. I first was testing the connections using a MacBook Air where I had to use the USB to ethernet USB adaptor. Using iperf, I was able to determine that I was typically able to get in excess of 120Mbits/s to the room in question. Using a weak wifi signal, I was only able to get Kbits via WiFi.

My plan was to attach an airport express to the Devolo dLan device and then the iMac to the spare ethernet port on the airport express. This way I could use the iMac and also extend WiFi coverage to that area of my home.

I initially tested my intended setup with a MacBook Air. Everything worked just fine. However, when I attached the ethernet cable to my Airport Express it did not appear to see the ethernet connection. I then tried my iMac, it too thought there was a problem with the ethernet adaptor. Initially, failing to get an IP address and eventually assigning itself something like 169.254.127.40 and mask 255.255.0.0. On subsequent tries it will assign a 169.254.x.y where x and y have different values than the earlier tests.

At first I thought I might have a cable problem. I verified the cable was good. To confirm it wasn't a problem with the iMac, I tried my Mac Book Pro. However, it too had the same behaviour as the iMac. Since it was working with the Mac Book Air, I then tried the using the USB ethernet adaptor with the iMac and the Mac Book Pro. They both recognize the home network and operate smoothly over it when the Devolo dLan device is connected to them via the Apple USB to ethernet adaptor. But they do not recognize the network when attached via their ethernet ports.

You might ask why not use the USB adaptor. The problem is it can only be attached to the iMac it does not allow me to extend my wifi coverage. Ideally I would like to do both.

Any thoughts or suggestions as to why my ethernet connection would only work with the USB adaptor?

 

[drsox]

I am having an ethernet connectivity problem, where my iMac and Mac Book Pro cannot connect to my home lan when I plug the ethernet cable directly into their ethernet ports. However, if I plug the ethernet cable into an apple usb to ethernet adaptor and connect via the iMac or MBP USB port, every thing works fine. My suspicion is that something with the DHCP handshake is timing out when connected via the computers ethernet adapter as opposed to using apples USB to ethernet adaptor.

I am trying to use Devolo dLan powerline adaptors to run an ethernet connection to a room where I have poor wifi signal. Ideally I would like to locate an airport express and an iMac in the room. I have both Devolo dLan 500 and dLan 200 adaptors. I first was testing the connections using a MacBook Air where I had to use the USB to ethernet USB adaptor. Using iperf, I was able to determine that I was typically able to get in excess of 120Mbits/s to the room in question. Using a weak wifi signal, I was only able to get Kbits via WiFi.

My plan was to attach an airport express to the Devolo dLan device and then the iMac to the spare ethernet port on the airport express. This way I could use the iMac and also extend WiFi coverage to that area of my home.

I initially tested my intended setup with a MacBook Air. Everything worked just fine. However, when I attached the ethernet cable to my Airport Express it did not appear to see the ethernet connection. I then tried my iMac, it too thought there was a problem with the ethernet adaptor. Initially, failing to get an IP address and eventually assigning itself something like 169.254.127.40 and mask 255.255.0.0. On subsequent tries it will assign a 169.254.x.y where x and y have different values than the earlier tests.

At first I thought I might have a cable problem. I verified the cable was good. To confirm it wasn't a problem with the iMac, I tried my Mac Book Pro. However, it too had the same behaviour as the iMac. Since it was working with the Mac Book Air, I then tried the using the USB ethernet adaptor with the iMac and the Mac Book Pro. They both recognize the home network and operate smoothly over it when the Devolo dLan device is connected to them via the Apple USB to ethernet adaptor. But they do not recognize the network when attached via their ethernet ports.

You might ask why not use the USB adaptor. The problem is it can only be attached to the iMac it does not allow me to extend my wifi coverage. Ideally I would like to do both.

Any thoughts or suggestions as to why my ethernet connection would only work with the USB adaptor?

Too much info in this - all squashed together.

List out the config that you want to work including ALL the units and I'll see if I can help. I used to have Devolo stuff - they work fine but only at 15% of rated speed in my experience. You have a DHCP problem sure enough. Where is your DHCP router ?

 

[rkv]

Too much info in this - all squashed together.

List out the config that you want to work including ALL the units and I'll see if I can help. I used to have Devolo stuff - they work fine but only at 15% of rated speed in my experience. You have a DHCP problem sure enough. Where is your DHCP router ?

Thank you for the offer of help. First I will show you a configuration which is working. Then I will show two configurations which I have tried and would prefer but do not currently work.

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Working but suboptimal Configuration A.

[1]: Internet via Wifi access point - I have no control or access to the physical device. It is a source of WiFi within the building. It is not secure, but requires an individual account to login. This is accomplished by browser redirection to a portal where one provides the account info which establishes a connection.

[2]: Airport Express - Located in area of apartment which has good Wifi connectivity to [1]. I have configured the Airport Express as "Connect Using: DHCP" and "Network Mode: Join a wireless network". The DHCP connection provides an ip address of 10.0.5.32 or some variant where the last digit change and Router Address and DNS Server address of 10.0.0.1.

[3]: dLan AV500 - connected by ethernet cable to local lan port on [2].

[4]: dLan AV500 = which has been networked with [3].

[5]: MacPro OS x 10.8.5 Ethernet port 1 - MacPro set to using DHCP and it gets an ip address of 10.0.4.156 with subnet mask of 255.255.0.0 and Router and DNS of 10.0.0.1.

Configuration A allows the MacPro to have access to the buildings WiFi as if it were connected to the WiFi directly. Establishing the connection at the MacPro involves a Safari window being popped to allow the input of the account number on the building portal redirection page.

The problem is that this does not extend the WiFi network for the purposes of other laptops and phones which I would like to have access to the internet.

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Configuration B - is what I thought would be my preferred configuration but failed to work

[1]: Internet via Wifi access point - I have no control or access to the physical device. It is a source of WiFi within the building. It is not secure, but requires an individual account to login. This is accomplished by browser redirection to a portal where one provides the account info which establishes a connection.

[2]: Airport Express - Located in area of apartment which has good Wifi connectivity to [1]. I have configured the Airport Express as "Connect Using: DHCP" and "Network Mode: Join a wireless network". The DHCP connection provides an ip address of 10.0.5.32 or some variant where the last digit change and Router Address and DNS Server address of 10.0.0.1.

[3]: dLan AV500 - connected by ethernet cable to local lan port on [2].

[4]: dLan AV500 = which has been networked with [3].

[5]: Airport TimeCapsule software version 7.6.4 attached to [4] via the TimeCapsule wlan ethernet port.

Under configuration B, the Time Capsule never gets an ip address and indicates that it is not attached to the internet. I haven't tried manually setting the ip since I don't have any means of guaranteeing that I wouldn't have a conflict.

If configuration B would have worked I would have had the Time Capsule provide it's own wireless network.



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Configuration C - is an alternative to B which would get me most of what I wanted. Other than I would need to position my MacPro in the distant room rather than the iMac I originally intended to use there.

[1]: Internet via Wifi access point - I have no control or access to the physical device. It is a source of WiFi within the building. It is not secure, but requires an individual account to login. This is accomplished by browser redirection to a portal where one provides the account info which establishes a connection.

[2]: Airport Express - Located in area of apartment which has good Wifi connectivity to [1]. I have configured the Airport Express as "Connect Using: DHCP" and "Network Mode: Join a wireless network". The DHCP connection provides an ip address of 10.0.5.32 or some variant where the last digit change and Router Address and DNS Server address of 10.0.0.1.

[3]: dLan AV500 - connected by ethernet cable to local lan port on [2].

[4]: dLan AV500 = which has been networked with [3].

[5]: MacPro Ethernet port 1 attached to [4]. This works as in configuration A. However, the enhancement is to attach the Time Capsule to Ethernet port 2.
MacPro is configured for sharing of internet on Ethernet 1 to computers on Ethernet 2.

[6]: Airport TimeCapsule software version 7.6.4 attached to [5] via the TimeCapsule wlan ethernet port. Under this configuration the Ethernet port to appears to remain red under the Network System Preferences panel on the MacPro. The time capsule never gets an ip address. I also tried manually setting the ip of the MacPro ethernet 2 and the Time Capsule to 192.168.16.1 and 192.168.16.2. Computers downstream to the TimeCapsule get ip addresses from the Time Capsule. However, they never appear to have access to the MacPro's internet connection.

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Any suggestions you might have for either attaching the TimeCapsule to the dLAN device as in configuration B or to the MacPro as in Configuration C would be appreciated.

Thanks.

 

[brand]

You are misusing the term "Power Over Ethernet"

Power Over Ethernet ≠ Power line communication

 

[drsox]

Thank you for the offer of help. First I will show you a configuration which is working. Then I will show two configurations which I have tried and would prefer but do not currently work.

UPDATE :

Have you tried using the TC to extend the Wireless Network and not use the Devolo at all ?

ORIGINAL POST :

OK. Now I understand your config better. Inevitably there are some further questions.

A. How have you configured the Airport Express for Network ? You have "Connect Using: DHCP" for Internet and "Network Mode: Join a wireless network" for Wireless, but there's another tab for Network - what does that say ?
Is this a V1 AE with only the one LAN port ?

B. What IP addresses do the Devolo devices have ? Do they also have addresses in the range 10.0.4.X ?

What's happening here is that all your own devices are being managed by this inaccessible WiFi Access Point. That's why your MacPro address is on a subnet of the main 10.0.0.0 network with the inaccessible WiFi Access Point having the IP address 10.0.0.1. Usually people want to have local control over their devices but that's for later maybe in your case.

If you can set the AE's Network tab to Router Mode - Off (Bridge Mode), then it might allow connections through the Devolo link. As it is now, is seems that the Devolo link isn't doing anything for you. Have you tested the MacPro's Internet connection by using only the Devolo link ?

If the Devolo link is working, then you might try this :
1. Connect the TC's WAN port to the Devolo using DHCP for Internet and Router Mode - Off (Bridge Mode) for Network.
2. Connect the MacPro to any LAN port on the TC.

Now see is there's an Internet connection through the LAN/WAN ports.

3. Setup the Wireless on the TC to Create a Wireless Network (different to the other one) and see if your other WiFi devices can connect to this. This might connect through the TC and the Devolo link to the AE.

Make sure you can undo all this if it doesn't work first time around ! Write down all the original settings.

 

[rkv]

You are misusing the term "Power Over Ethernet"

Power Over Ethernet ≠ Power line communication

My apologies, I actually should have known that. I've edited the posts subject line.

Also note, my most recent post is an accurate reflection of my current problem in that the dLan devices are working at some level. The difference is that when I was experimenting for the initial post I was simply trying to test throughput of the dLan device between various rooms. So I was testing by trying to establish a Mac to Mac connection. Most recently, I've got a "working" implementation for my original goal which was to extend a WiFi connection via the Devolo devices to an area of my apartment which does not have WiFi connectivity.

However, I have problems when I try to connect the dLan device to an Apple Time Capsule. Or probably completely unrelated I try to share the internet connection via a MacPro's second ethernet port. I'm standing by to see what advice drsox will be offering.

 

[drsox]

My apologies, I actually should have known that. I've edited the posts subject line.

Also note, my most recent post is an accurate reflection of my current problem in that the dLan devices are working at some level. The difference is that when I was experimenting for the initial post I was simply trying to test throughput of the dLan device between various rooms. So I was testing by trying to establish a Mac to Mac connection. Most recently, I've got a "working" implementation for my original goal which was to extend a WiFi connection via the Devolo devices to an area of my apartment which does not have WiFi connectivity.

However, I have problems when I try to connect the dLan device to an Apple Time Capsule. Or probably completely unrelated I try to share the internet connection via a MacPro's second ethernet port. I'm standing by to see what advice drsox will be offering.

It's done

 

[rkv]

DRSOX, thanks. Here are a some answers. I will have to report back tomorrow on the additional testing I need to do.

Have you tried using the TC to extend the Wireless Network and not use the Devolo at all ?

No, but I will report on that tomorrow.

A. How have you configured the Airport Express for Network ? You have "Connect Using: DHCP" for Internet and "Network Mode: Join a wireless network" for Wireless, but there's another tab for Network - what does that say ? Is this a V1 AE with only the one LAN port ?

I am using Airport Utility 6.3.1. And I do not see an additional tab. It shows "Base Station", "Internet", "Wireless", and "AirPlay" as different tabs or panes. The "Internet" tab only had "Renew DHCP" and "Internet Options" the later to set IPV6 settings. If the "Wireless" tab is set to"Join a wireless network" then the "Network" tab you mention is not a visible tab. It only appears when one "Extends a wireless..." or "Create a wireless...".

The AE is a relatively new version that comes with a power cord. It has a single WAN and a single LAN port.

B. What IP addresses do the Devolo devices have ? Do they also have addresses in the range 10.0.4.X ?

The Devolo devices do not have visible IP addresses. At least not visible from dLAN Cockpit which is their current configuration software. I believe this is the way it is supposed to be. Because these ethernet over power devices are supposed to be invisible to the network.

If you can set the AE's Network tab to Router Mode - Off (Bridge Mode), then it might allow connections through the Devolo link. As it is now, is seems that the Devolo link isn't doing anything for you. Have you tested the MacPro's Internet connection by using only the Devolo link ?

There is not AE Network tab when "Wireless" is set to "Join a wireless network". I believe that "Join a Wireless Network" forces bridge mode, since dhcp to the LAN port of the AE gives one and IP address in the 10.0.4.x range.

The Devolo device is extending the LAN port of the AE to another room on a different floor via wall plugs.

Configuration A works. That is the buildings WiFi is extended via in wall electrical to a different location and the Ethernet port on my MacPro. Note, this is somewhat different than my initial post. In my initial post I was testing throughput between rooms over the electrical wiring by using a MacBook and the MacPro. This is when the MacBooks would not recognize that they were connected to the other computer when using their builtin ethernet port. I had to use the Ethernet to USB adapter for some reason in order for the MacBook to see an ethernet connection. Note this is when it was computer to computer. They all recognize the dLan ethernet cable as providing a network connection in configuration A .

If the Devolo link is working, then you might try this :
1. Connect the TC's WAN port to the Devolo using DHCP for Internet and Router Mode - Off (Bridge Mode) for Network.
2. Connect the MacPro to any LAN port on the TC.

I had previously tried this and it works. The problem is that it exposes my in house network to a building with fifty apartments in it. Also, one of the reasons I wanted to have a private network is that besides my MacPro and iMac, I have five laptops (MacBook, MacBook Pro, and MacBook Air) as well as three iPads all to which I want to stream video from the MacPro. I don't want this traffic going over the buildings WiFi network.

3. Setup the Wireless on the TC to Create a Wireless Network (different to the other one) and see if your other WiFi devices can connect to this. This might connect through the TC and the Devolo link to the AE.

I need to try your item 3 variant. I haven't done that. I will report back tomorrow.

To some extent I've moved on with the original problem in that I haven't addressed why MacBook not seeing the MacPro with hardwired ip addresses over the dLAN device. Although that isn't critical to the operational configuration I would like. Additionally, I haven't resolved why I can't share my internet connection from the MacPro to my TC. I suspect the later has to do with DHCP. However, I've even tried to hardwire the IP addresses without success. However, that to isn't critical if the TC will talk to the dLAN devices.

In any event, I will try that configuration with all of my computers on the LAN side of the TC to see how that works and report back tomorrow.

Thanks again for your help.

 

[drsox]

DRSOX, thanks. Here are a some answers.

OK. I think that you will need to use the TC to create a new internal network so that all your devices are hidden from the AE and from the shared WiFi Internet source. As you have stated that the Devolo connection is working, then this new network will start with the TC connected to the Devolo.

You need to setup the TC to create a new network but using DHCP for the Internet setting tab (with the Devolo link connected to the WAN port). Set the Wireless to Create a Wireless Network (something completely new) and set the Network tab to DHCP. This gives you the ability to chose a different network (e.g.192.168.123.X). If you chose DHCP and NAT then there seems to be no choice over network type. I'm not sure if the DHCP only option exposes your internal connections. Maybe something to experiment with. I would start with the DHCP and NAT option, but you might get the double NAT warning from the TC (usually can be ignored unless you run apps that need remote connections)

There used to be a good guide to cascading router setups on the SmallNetBuilder site, so I'll go and look for it in the meantime.

UPDATE : Here's the guide : http://www.smallnetbuilder.com/content/view/24428/53/ , but in your case there are only 2 routers, not the three as outlined. You will have the AE/shared WiFi Internet source as the top level one and the TC as the second level one. Hopefully the "auto" setup routines in the TC will avoid having to delve into any of the detailed options.

 

[rkv]

DRSOX, thanks for your continued assistance in answering my questions. Things are now working. I do however have a few questions. Hopefully, these are the last on this thread.

The smallnetbuilder article was helpful. I could swear I tried taking the Devolo directly to the WAN port of the TC before and could only get it to work in bridge mode. However, it is now working just fine with the DHCP mode setting under the "Internet" tab setting in Airport Utility.

I may be misinterpreting you last post. The WAN port on the TC via DHCP is getting an ip address like 10.0.3.x. If I use the "DHCP Only" setting in the Network tab, I do not have a choice of network ip. The first three segments default to 10.0.3. I am only able to change the range of the fourth level. However, if I use "DHCP and NAT", then I can pick a "10.0", "172.16", or "192.168" address range. This seems to be the opposite of what you said.

In any event, "DHCP and NAT" does work from the standpoint of web access and email. I do get a "Double NAT" warning. Since I have several teenagers who are online gamers and I suspect use torrents from time to time, I am wondering if this is likely to be an issue for them. For the time being I have told the TC to ignore the Double NAT error. I will wait to see if children complain.

My limited understanding is that Double NAT would interfere with the indirection mechanism which allows for the outside world to contact a specific port or application on a computer on the local LAN. I do use "Back to My Mac" occasionally. The iCloud preference pane is warning that it might be slow. Is Double NAT more a performance issue or does it stop most things which would rely on such communication from working in their entirety?

With respect to one of DRSOX's questions in an earlier post, I have also confirmed that using the Devolo dLAN devices is about two to three times faster than having the AE act as a repeater to extend the buildings WiFi network.

As an aside the image below is what I am seeing from Airport Utility after I told it to ignore Double NAT. I thought it was a cute way of Apple providing visual queuing that even though the status was green my TC was suffering from Double NAT. This is really what I saw. However, I expect it's a bug as opposed to a feature.

DRSOX, again many thanks. I now have the "working" network configuration I originally set out for. Hopefully, Double NAT will turn out to not be an issue.

 

[drsox]

DRSOX, thanks for your continued assistance in answering my questions. Things are now working. I do however have a few questions. Hopefully, these are the last on this thread.


DRSOX, again many thanks. I now have the "working" network configuration I originally set out for. Hopefully, Double NAT will turn out to not be an issue.

Glad to hear it's working to your satisfaction to a degree. I tested the DHCP only vs DHCP and NAT options on my config and what I quoted is what I saw, so maybe my config is different enough for it to be reversed (or maybe it's just dyslexia - don't think I have that). (Just checked it again and it is as I said for my config - I have three AEs in Bridge mode behind an AE in Router mode. You have a TC in Router mode behind an AE in Bridge mode behind a WiFi Access Point in Router mode). If DHCP and NAT is workable, then that does give better isolation from your neighbours, but double NAT will be an issue if you or yours do stuff like MMOG that rely on specific port access.

Also glad to see that Devolo is working OK for you. I gave up on Devolo and ran CAT6 everywhere, but it can work.

The Apple AU diagram is correct as it ignores "errors" that you have told it to forget, so green lights all round are good news - it means everything else apart from Double NAT is working OK.

Glad to help.