Tag: network manager

How to create bridges on bonds (with and without VLANs) using NetworkManager

Some production systems you face might make use of bonded network connections that you need to bridge in order to get VMs onto them. That bond may or may not have a native VLAN (in which case you bridge the bond), or it might have VLANs on top (in which case you want to bridge the VLANs), or perhaps you need to do both.

Let’s walk through an example where we have a bond that has a native VLAN, that also has the tagged VLAN 123 on top (and maybe a second VLAN 456), all of which need to be separately bridged. This means we will have the bond (bond0) with a matching bridge (br-bond0), plus a VLAN on the bond (bond0.123) with its matching bridge (br-vlan123). It should look something like this.

+------+   +---------+                           +---------------+
| eth0 |---|         |          +------------+   |  Network one  |
+------+   |         |----------|  br-bond0  |---| (native VLAN) |
           |  bond0  |          +------------+   +---------------+
+------+   |         |                                            
| eth1 |---|         |                                            
+------+   +---------+                           +---------------+
            | |   +---------+   +------------+   |  Network two  |
            | +---| vlan123 |---| br-vlan123 |---| (tagged VLAN) |
            |     +---------+   +------------+   +---------------+
            |                                                     
            |     +---------+   +------------+   +---------------+
            +-----| vlan456 |---| br-vlan456 |---| Network three |
                  +---------+   +------------+   | (tagged VLAN) |
                                                 +---------------+

To make it more complicated, let’s say that the native VLAN on the bond needs a static IP and to operate at an MTU of 1500 while the other uses DHCP and needs MTU of 9000.

OK, so how do we do that?

Continue reading How to create bridges on bonds (with and without VLANs) using NetworkManager

How to create Linux bridges and Open vSwitch bridges with NetworkManager

My virtual infrastructure Ansible role supports connecting VMs to both Linux and Open vSwitch bridges, but they must already exist on the KVM host.

Here is how to convert an existing Ethernet device into a bridge. Be careful if doing this on a remote machine with only one connection! Make sure you have some other way to log in (e.g. console), or maybe add additional interfaces instead.

Export interfaces and existing connections

First, export the the device you want to convert so we can easily reference it later (e.g. eth1).

export NET_DEV="eth1"

Now list the current NetworkManager connections for your device exported above, so we know what to disable later.

sudo nmcli con |egrep -w "${NET_DEV}"

This might be something like System eth1 or Wired connection 1, let’s export it too for later reference.

export NM_NAME="Wired connection 1"

Create a Linux bridge

Here is an example of creating a persistent Linux bridge with NetworkManager. It will take a device such as eth1 (substitute as appropriate) and convert it into a bridge. Note that we will be specifically giving it the device name of br0 as that’s the standard convention and what things like libvirt will look for.

Continue reading How to create Linux bridges and Open vSwitch bridges with NetworkManager

Telstra NextG working with MF626 USB modem

Essentially, these devices are detected as a SCSI CD device so that Windows and Mac users can install the drivers and software to make the device work and connect to the net. They then switch product ID to activate the device as a modem. Unfortunately this didn’t work properly in Ubuntu, and would only detect as a mass storage device. With this fix, it can be hot plugged and still work :-O

Thanks to a post in the Ubuntu forums, I finally got the Telstra NextG wireless working for a friend of Mike, on his Jaunty netbook.

Here’s what I did, for for future reference:

1) Install udev-extras which provides some extra hal scripts.
sudo apt-get install udev-extras

2) Install the Debian Sid i386 usb-modeswitch package, rather than build from scratch.
http://packages.debian.org/sid/usb-modeswitch
sudo dpkg -i usb-modeswitch_0.9.7-1_i386.deb

3) Uncommented the “ZTE MF626” entry of the usb-modeswitch config (including the # comments!).
sudo vim /etc/usb_modeswitch.conf

ZTE MF628+ (tested version from Telia / Sweden)
ZTE MF626

Contributor: Joakim Wennergren

DefaultVendor= 0x19d2
DefaultProduct= 0x2000

TargetVendor= 0x19d2
TargetProduct= 0x0031

MessageEndpoint=0x01
MessageContent=”55534243123456782000000080000c8501 0101180101010101000000000000″

4) Create new HAL rule to activate the device as a modem.
sudo vim /usr/share/hal/fdi/information/20thirdparty/20-zte-mf626.fdi

<!– -*- SGML -*- –>
<deviceinfo version=”0.2″>
<device>
<!– ZTE MF626 HSDPA USB Modem –>
<match key=”@info.parent:usb.vendor_

id” int=”0x19d2″>
<match key=”@info.parent:usb.product_id” int=”0x0031″>
<match key=”@info.parent:usb.interface.number” int=”3″>
<append key=”modem.command_sets” type=”strlist”>GSM-07.07</append>
<append key=”modem.command_sets” type=”strlist”>GSM-07.05</append>
<append key=”info.capabilities” type=”strlist”>modem</append>
</match>
</match>
</match>
</device>
</deviceinfo>

5) Create a new udev rule to auto run usb_modeswitch when the device is plugged in.
sudo vim /etc/udev/rules.d/90-zte.rules

ACTION!=”add”, GOTO=”ZTE_End”

SUBSYSTEM==”usb”, SYSFS{idProduct}==”2000″, SYSFS{idVendor}==”19d2″, GOTO=”ZTE_ZeroCD”

LABEL=”ZTE_ZeroCD”
RUN+=”/usr/sbin/usb_modeswitch -W -c /etc/usb_modeswitch.conf”

LABEL=”ZTE_End”

6) Remove the HAL FDI cache and reboot.
sudo rm /var/cache/hald/fdi-cache
sudo reboot

7) Then after a reboot, I plug in the device, wait for it to go blue, then connect to Telstra (Next G Card) in Network Manager.

Works!

Internet by way of the Dodo

I’ve been helping a friend at work get Linux on her laptop. I installed Ubuntu Jaunty Jackalope 9.04 as this is quite good for new users (and we have a mirror at work). She connects to the Internet like many people these days, using a USB 3G modem. Her provider is Dodo, which actually uses the Optus network.

Anyway, I was pleasantly surprised when I plugged in the device and Network Manager popped up a wizard prompting for a new connection. Yep, the device just works on Linux.

Unfortunately there is no “Dodo” profile the Network Manager, but knowing it runs on Optus network I chose “Optus 3G”. I booted into Windows to get the APN, as it will be different to Optus. After changing that I just needed to click on the Network Manager applet and tell it to connect. But it didn’t work. It tried to log on, everything goes green and then BAM. Nothing.

There was obviously something else that was needed. I checked the settings and saw that the Optus profile had DNS servers hard coded. I grabbed the DNS servers that dodo uses and put them in instead. This time everything worked and I could log on. Internet, she was a working.

So, for anyone already with Dodo or thinking about it, here are the settings I used.

Number: *99#
APN: dodolns1 (that's a letter "L")
Authentication: CHAP
DNS: 202.136.43.197, 202.136.42.229

You will need to register your account with Dodo first and activate it. After that, your Internet should work just fine by using these settings.

It seems that it’s often quite slow when compared to Windows, which I’m putting this down to the Linux driver. Speeds seem to range between 600b/sec and 50kb/sec, which is a little disappointing. It could just be signal or something else, I’m not sure. Still, it’s great that it works out of the box under Linux. Now if only I could get Mike’s friend’s Telstra stick to do the same! HAL rules here I come..

-c

Whatever did we used to do?

These days everyone wants a graphical interface for this and for that, including a network manager to well, manage your network connections. Back in the days when wireless hardly ever worked in Linux anyway, who cared? But now that life is more than just DHCP on eth0 things need to get more fancy. Now that Linux has awesome wireless support, we’ve also moved to mobile broadband with a much faster pace than I ever expected. That’s all good.

Dan Williams has just blogged about the new NetworkManager 0.7.1 release which contains a slew of updates and improvements. I wonder whether the issue of suspending the laptop then resuming somewhere else and having it re-detect wireless access points in the new location has been fixed or not. Wait.. laptops can suspend and resume now too? Boy!

-c