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Old 09-23-2014, 04:30 PM   #1
rnturn
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No default route configured w/ wired net connection managed by NetworkManager


After running into problems getting a proper wired network connection set up using NetworkManager, I'm wondering if anyone has gotten this to work.

Some background:

The wired connection is using a fixed IP address outside our firewall and is wired directly to our Uverse gateway. I've specified the same DNS servers that are being used inside the firewall in 'forwarders.conf'. The `/etc/resolv.conf' file has the same IP addresses for the DNS servers as well. I'm trying to set this system up the same way that our firewall (an older RedHat system w/ no GUI) has been configured though on the laptop I'm using NetworkManager. (Mainly because the laptop is used via the wireless the majority of the time and I'm trying to stick with a single method of setting up the network connections. So far, NetworkManager hasn't been a problem when used to set up wireless connections.)

Now that you've read this far, here's the mysterious thing. On the firewall I see:
Code:
# netstat -r
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
aaa.bbb.ccc.168  *               255.255.255.248 U        40 0          0 eth1
192.168.13.0     *               255.255.255.0   U        40 0          0 eth0
127.0.0.0        *               255.0.0.0       U        40 0          0 lo
default         aaa-bbb-ccc-174. 0.0.0.0         UG       40 0          0 eth1
#
What I'm seeing on the laptop is:
Code:
# netstat -r
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
aaa.bbb.ccc.168  *               255.255.255.248 U         0 0          0 eth0
#
Hmm... no default route. Even though it's specified in the NetworkManager GUI for the wired connection using eth0. Everything looks fine if I go into YaST and use the traditional `ifup'-style setup.

Other info: I'm using a Dell laptop running OpenSUSE 12.2. Yes... I'm aware that there are newer versions. I'm hoping the 12.2 NetworkManager isn't broken though, given what I saw when I tried using it for the wired connection, I suspect it is.

Q: Am I stuck with switching back and forth between `ifup' and `NetworkManager' when I change from a wired to a wireless connection?


TIA...

--
Rick
 
Old 09-23-2014, 05:45 PM   #2
suicidaleggroll
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I use a static IP for the wired connection on my OpenSUSE laptops configured through NetworkManager all the time, never had a problem with it. I'm a little confused by your description of the setup though, how exactly is everything wired and supposed to be routed? What did you fill in for your IP, mask, and gateway on the laptop?

Last edited by suicidaleggroll; 09-23-2014 at 05:46 PM.
 
Old 09-24-2014, 01:10 AM   #3
rnturn
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Quote:
Originally Posted by suicidaleggroll View Post
I'm a little confused by your description of the setup though, how exactly is everything wired and supposed to be routed? What did you fill in for your IP, mask, and gateway on the laptop?
Hmm... I'm not sure why that description was confusing. I did delete some stuff before posting that I thought might have been confusing. (Maybe I shouldn't have.) I noticed the non-existent default route while I was debugging why name resolution wasn't working. (It was a traceroute command that finally indicated that something about the route was in error.)

To reiterate the basic setup:

I'm using the exact same settings as I used on the firewall external network adapter: mask, network, default route... everything's all the same -- except, of course , for the IP address. Both interfaces have fixed IP addresses: firewall = aaa.bbb.ccc.169, laptop = aaa.bbb.ccc.170. For whatever reason, NetworkManager did not define the default route as I showed in the `netstat -r' output despite the fact that it was defined in the NM GUI. Seems to me like the tool is broken if it doesn't do that.

Q: Could any previous use of the old ifup tools in the past left something behind that is confusing NetworkManager when it tries to work with the wired connection?

For now I'm using the traditional ifup-style configuration (through YaST) and it's working but only for the wired connection. I'd really like to standardize on one tool or the other. Since NetworkManager seems to be the preferred tool that seems to be the way to go. It does a good job of configuring the wireless interface without any trouble (but only the wireless).

Hope this is a little clearer now.

Any ideas?

--
Rick
 
Old 09-24-2014, 10:11 AM   #4
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What is the actual layout of your network? Do you have one IP from your ISP or a block? Dynamic or static? Are you using a simple modem from your ISP or is it actually a NAT that's setting up its own LAN? DHCP or no? Is the laptop wired in parallel with the firewall (both attached to something else? What?), or in series (laptop attached to output of firewall)? Or is the laptop wired in place of the firewall? In which case why is it using a different IP? Is the firewall setting up its own LAN to which every other machine connects? Are you trying to do the same thing with the laptop as well?
 
Old 09-24-2014, 10:26 AM   #5
rnturn
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Quote:
Originally Posted by suicidaleggroll View Post
What is the actual layout of your network? Do you have one IP from your ISP or a block? Dynamic or static? Are you using a simple modem from your ISP or is it actually a NAT that's setting up its own LAN? DHCP or no? Is the laptop wired in parallel with the firewall (both attached to something else? What?), or in series (laptop attached to output of firewall)? Or is the laptop wired in place of the firewall? In which case why is it using a different IP? Is the firewall setting up its own LAN to which every other machine connects? Are you trying to do the same thing with the laptop as well?
I'm struggling mightily to see what any of these questions have to do with NetworkManager's inability to set up the default route. My only goal was to be able to configure the laptop using one of the block of five static IP addresses to be able to perform security and web site testing. Details of the wiring of our LAN really isn't germain to the problem.

Let's just call this question "solved" via a (rather unsatisfying) workaround.

Later...

Update: I seem to have found a better solution: Go into YaST -> Network Devices -> Network Settings. Make sure you're running the "traditional/ifup" method of network configuration. Delete the settings for all interfaces. Delete the routing, DNS, and anything else associated with the interfaces. Save/exit/etc. Rerun Yast and change the network configuration method to NetworkManager. Save/exit (again). Then go into the KDE NetworkManager GUI. Delete all the wired connections settings. Redefining the wired connection settings, saving, and reconnecting did the trick. This tells me that there is something about the configuration files that gets NetworkManager confused when it wasn't the one that created the information in that file.

Last edited by rnturn; 09-24-2014 at 11:11 AM. Reason: Better fix found.
 
Old 09-24-2014, 11:18 AM   #6
suicidaleggroll
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You have to understand, 99% of questions/problems posted on this site stem from a misconfiguration or a misunderstanding of the tool. Without knowing the physical layout of the network, there's no way we can know if your problem is being caused by a misconfiguration or a problem in NetworkManager.

I don't know why it wouldn't be setting up a default route, it's never been a problem on my machines doing the same thing on the same OS. You did disable wireless before diving into the wired config right?

What is the output if "ip route"?

Last edited by suicidaleggroll; 09-24-2014 at 11:39 AM.
 
Old 09-24-2014, 12:26 PM   #7
rnturn
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Quote:
Originally Posted by suicidaleggroll View Post
You have to understand, 99% of questions/problems posted on this site stem from a misconfiguration or a misunderstanding of the tool. Without knowing the physical layout of the network, there's no way we can know if your problem is being caused by a misconfiguration or a problem in NetworkManager.
I would have thought that being able to get the wired connection working using ifup would pretty much exonerate the wiring.

Quote:
I don't know why it wouldn't be setting up a default route, it's never been a problem on my machines doing the same thing on the same OS.
My guess is that you never used the ifup tools to configure your connections. Once I blew away any trace of network configuration using the ifup method, things started working. I believe it's a flaw in NetworkManager that was causing it to choke when it saw an entry that it hadn't created. Not knowing anything about the guts of NM, one can envision it being something as silly as an extra space in the information that caused NM to get confused and refuse to use it resulting in no route.

Quote:
You did disable wireless before diving into the wired config right?
Yes, though I'm not certain it would have been absolutely necessary (though it surely would have complicated any debugging had I needed to do that). After getting the wired connection configured, though, you can re-enable wireless. I just need to keep only one connection active via the NM GUI in the panel. If both wired/wireless are active the wired connection's default route seems to win out.

Quote:
What is the output if "ip route"?
It's looking as I expected depending on which interface I'm using. The routing looks fine for the wired connection; there's now actually an entry for default ("default aaa.bbb.ccc.174 dev eth0 proto static") that was not there before.

Cheers...

Last edited by rnturn; 09-24-2014 at 12:38 PM. Reason: corrected typo
 
  


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