Tag Archives: network configuration

Configuring Interface Bonding on Debian (Wheezy)

This is a brief article detailing the steps to configure network interface bonding on Debian Wheezy (7.0 stable). The procedure is very different from RHEL/CentOS. I will be configuring active-backup (i.e. failover) mode bonding - there are other modes available, including round-robin load-balanced, LACP aggregation, etc. Read /usr/share/doc/ifenslave-2.6/README.Debian or http://www.kernel.org/doc/Documentation/networking/bonding.txt for further information.

First, verify via ifconfig that your two slave interfaces are available - I’ll be bonding eth0 and eth1 into a bond called bond0:

# ifconfig eth0
...
# ifconfig eth1
...

# ifconfig eth0

...

# ifconfig eth1

...

Install the ifenslave package:

# aptitude install ifenslave

1	# aptitude install ifenslave

Next, stop networking. As you’re stopping networking, ensure that you’re connected to your host via a console of some form:

# invoke-rc.d networking stop

1	# invoke-rc.d networking stop

Modify /etc/network/interfaces. Remove (or comment out) any existing configuration for your slave interfaces (eth0 and eth1), and configure your new bond0 interface appropriately:

# vi /etc/network/interfaces
...
auto bond0
iface bond0 inet static
    address 192.168.122.15
    netmask 255.255.255.0
    gateway 192.168.122.1
    slaves eth0 eth1
    bond_mode active-backup
    bond_miimon 100
    bond_downdelay 200
    bond_updelay 200

# vi /etc/network/interfaces

...

auto bond0

iface bond0 inet static

address 192.168.122.15

netmask 255.255.255.0

gateway 192.168.122.1

slaves eth0 eth1

bond_mode active-backup

bond_miimon 100

bond_downdelay 200

bond_updelay 200

bond_miimon is the MII link monitoring frequency in milliseconds, and bond_{down,up}delay are the time, in milliseconds, to wait before disabling or enabling an interface in the bond (to safeguard against flapping), and should be a multiple of the bond_miimon value. You can adjust these values to suit your needs. These bond_<parameter> directives correlate to the <parameter> directives passed to the bonding module itself.

Once configured, start networking:

# invoke-rc.d networking start

1	# invoke-rc.d networking start

There is no need to fiddle with module loading (editing /etc/modules, creating a file under /etc/modprobe.d, etc.) - the ifenslave-2.6 package deposits scripts to do this for us. Take a look at /etc/network/if-pre-up.d/ifenslave to see this being done.

You can see the other scripts installed by ifenslave-2.6 with a dpkg -L:

# dpkg -L ifenslave-2.6 | grep etc
/etc
/etc/network
/etc/network/if-pre-up.d
/etc/network/if-pre-up.d/ifenslave
/etc/network/if-post-down.d
/etc/network/if-post-down.d/ifenslave
/etc/network/if-up.d
/etc/network/if-up.d/ifenslave

# dpkg -L ifenslave-2.6 | grep etc

/etc

/etc/network

/etc/network/if-pre-up.d

/etc/network/if-pre-up.d/ifenslave

/etc/network/if-post-down.d

/etc/network/if-post-down.d/ifenslave

/etc/network/if-up.d

/etc/network/if-up.d/ifenslave

Running ifconfig -a should now show the correct network configuration:

# ifconfig -a
bond0     Link encap:Ethernet  HWaddr 52:54:00:14:6b:b3  
          inet addr:192.168.122.15  Bcast:192.168.122.255  Mask:255.255.255.0
          inet6 addr: fe80::5054:ff:fe14:6bb3/64 Scope:Link
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
          RX packets:6221 errors:0 dropped:698 overruns:0 frame:0
          TX packets:3253 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:5172756 (4.9 MiB)  TX bytes:397929 (388.6 KiB)
eth0      Link encap:Ethernet  HWaddr 52:54:00:14:6b:b3  
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:5512 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3253 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:5135486 (4.8 MiB)  TX bytes:397929 (388.6 KiB)
          Interrupt:11 Base address:0x2000 
eth1      Link encap:Ethernet  HWaddr 52:54:00:14:6b:b3  
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:709 errors:0 dropped:698 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:37270 (36.3 KiB)  TX bytes:0 (0.0 B)
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

# ifconfig -a

bond0 Link encap:Ethernet HWaddr 52:54:00:14:6b:b3

inet addr:192.168.122.15 Bcast:192.168.122.255 Mask:255.255.255.0

inet6 addr: fe80::5054:ff:fe14:6bb3/64 Scope:Link

UP BROADCAST RUNNING MASTER MULTICAST MTU:1500 Metric:1

RX packets:6221 errors:0 dropped:698 overruns:0 frame:0

TX packets:3253 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:0

RX bytes:5172756 (4.9 MiB) TX bytes:397929 (388.6 KiB)

eth0 Link encap:Ethernet HWaddr 52:54:00:14:6b:b3

UP BROADCAST RUNNING SLAVE MULTICAST MTU:1500 Metric:1

RX packets:5512 errors:0 dropped:0 overruns:0 frame:0

TX packets:3253 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:5135486 (4.8 MiB) TX bytes:397929 (388.6 KiB)

Interrupt:11 Base address:0x2000

eth1 Link encap:Ethernet HWaddr 52:54:00:14:6b:b3

UP BROADCAST RUNNING SLAVE MULTICAST MTU:1500 Metric:1

RX packets:709 errors:0 dropped:698 overruns:0 frame:0

TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:37270 (36.3 KiB) TX bytes:0 (0.0 B)

lo Link encap:Local Loopback

inet addr:127.0.0.1 Mask:255.0.0.0

inet6 addr: ::1/128 Scope:Host

UP LOOPBACK RUNNING MTU:16436 Metric:1

RX packets:0 errors:0 dropped:0 overruns:0 frame:0

TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:0

RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

You can also view the contents of /proc/net/bonding/bond0 to check the status of the bond:

# cat /proc/net/bonding/bond0 
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)
Bonding Mode: fault-tolerance (active-backup)
Primary Slave: None
Currently Active Slave: eth0
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 200
Down Delay (ms): 200
Slave Interface: eth0
MII Status: up
Speed: 100 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 52:54:00:14:6b:b3
Slave queue ID: 0
Slave Interface: eth1
MII Status: up
Speed: Unknown
Duplex: Unknown
Link Failure Count: 0
Permanent HW addr: 52:54:00:f2:28:8b
Slave queue ID: 0

# cat /proc/net/bonding/bond0

Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: fault-tolerance (active-backup)

Primary Slave: None

Currently Active Slave: eth0

MII Status: up

MII Polling Interval (ms): 100

Up Delay (ms): 200

Down Delay (ms): 200

Slave Interface: eth0

MII Status: up

Speed: 100 Mbps

Duplex: full

Link Failure Count: 0

Permanent HW addr: 52:54:00:14:6b:b3

Slave queue ID: 0

Slave Interface: eth1

MII Status: up

Speed: Unknown

Duplex: Unknown

Link Failure Count: 0

Permanent HW addr: 52:54:00:f2:28:8b

Slave queue ID: 0

Configuring Interface Bonding on CentOS/RHEL/OEL 6.x

In my previous article I wrote about configuring configuring network interface bonding under Debian Wheezy. Here, I’ll briefly outline the steps required to get the same configuration running under recent RHEL-flavoured distributions - namely CentOS 6.4 in my case.

I will be bonding eth0 and eth1 into a bond named bond0. Ensure that you’re connected to your host via a console. I’ll be using active-backup (i.e. failover) bonding, but there are other options available - see the Debian article for links to reference material for those.

First, create the ifcfg-bond0 configuration file:

# cd /etc/sysconfig/network-scripts
# vi ifcfg-bond0
DEVICE=bond0
IPADDR=192.168.122.12
NETMASK=255.255.255.0
GATEWAY=192.168.122.1
NM_CONTROLLED=no
BOOTPROTO=none
ONBOOT=yes
USERCTL=no

# cd /etc/sysconfig/network-scripts

# vi ifcfg-bond0

DEVICE=bond0

IPADDR=192.168.122.12

NETMASK=255.255.255.0

GATEWAY=192.168.122.1

NM_CONTROLLED=no

BOOTPROTO=none

ONBOOT=yes

USERCTL=no

Substitute relevant values as appropriate for your setup. Next, edit/create the ifcfg-eth{0,1} files. Note that these are created as slave interfaces (SLAVE=yes) with bond0 as the master interface (MASTER=bond0):

# vi ifcfg-eth0
DEVICE=eth0
USERCTL=no
ONBOOT=yes
NM_CONTROLLED=no
MASTER=bond0
SLAVE=yes
BOOTPROTO=none
# sed 's/eth0/eth1/' ifcfg-eth0 > ifcfg-eth1

# vi ifcfg-eth0

DEVICE=eth0

USERCTL=no

ONBOOT=yes

NM_CONTROLLED=no

MASTER=bond0

SLAVE=yes

BOOTPROTO=none

# sed 's/eth0/eth1/' ifcfg-eth0 > ifcfg-eth1

Note - that if NM_CONTROLLED is set, you should strictly define your HWADDR entries too at this step, for each interface. Configure the bonding module. miimon is the MII link monitoring frequency in milliseconds, {down,up}delay are the times, in milliseconds, to wait before disabling or enabling an interface in the bond (to safeguard against flapping), and should be a multiple of the miimon value. Note that /etc/modprobe.conf is deprecated in CentOS 6.x so an appropriate file should be created under /etc/modprobe.d - in our case, bonding.conf:

# vi /etc/modprobe.d/bonding.conf
alias bond0 bonding
options bond0 mode=active-backup miimon=100 downdelay=200 updelay=200

# vi /etc/modprobe.d/bonding.conf

alias bond0 bonding

options bond0 mode=active-backup miimon=100 downdelay=200 updelay=200

To test, manually load the module (and appropriate options - I see many tutorials with a simple modprobe bonding here - you’ll end up with the default bonding mode which is round-robin - not what we want):

# modprobe bonding mode=active-backup miimon=100 downdelay=200 updelay=200

1	# modprobe bonding mode=active-backup miimon=100 downdelay=200 updelay=200

And restart networking:

# service network restart

1	# service network restart

Verify that all is well with ifconfig -a, or more suitably a cat on /proc/net/bonding/bond0:

# cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.6.0 (September 26, 2009)
Bonding Mode: fault-tolerance (active-backup)
Primary Slave: None
Currently Active Slave: eth0
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 200
Down Delay (ms): 200
Slave Interface: eth0
MII Status: up
Speed: Unknown
Duplex: Unknown
Link Failure Count: 0
Permanent HW addr: 52:54:00:c1:77:fc
Slave queue ID: 0
Slave Interface: eth1
MII Status: up
Speed: 100 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 52:54:00:f3:11:1e
Slave queue ID: 0

# cat /proc/net/bonding/bond0

Ethernet Channel Bonding Driver: v3.6.0 (September 26, 2009)

Bonding Mode: fault-tolerance (active-backup)

Primary Slave: None

Currently Active Slave: eth0

MII Status: up

MII Polling Interval (ms): 100

Up Delay (ms): 200

Down Delay (ms): 200

Slave Interface: eth0

MII Status: up

Speed: Unknown

Duplex: Unknown

Link Failure Count: 0

Permanent HW addr: 52:54:00:c1:77:fc

Slave queue ID: 0

Slave Interface: eth1

MII Status: up

Speed: 100 Mbps

Duplex: full

Link Failure Count: 0

Permanent HW addr: 52:54:00:f3:11:1e

Slave queue ID: 0

Reboot the host at the earliest opportunity to verify that all is well after a reboot.

How to Upgrade from Solaris 10 to Solaris 11: Network Preparation

The aim of this series is to show the experienced Solaris system administrator how to transition from Solaris 10 to Solaris 11 immediately after initial installation of the operating system, as well as offering tips, tricks and insights into Solaris 11, which differs significantly from Solaris 10.

This article will cover the commands that will enable both servers to be networked and able to reach the internet.

Continue reading →

Toki Winter

Advanced UNIX for the experienced system administrator

Tag Archives: network configuration

Configuring Interface Bonding on Debian (Wheezy)

Configuring Interface Bonding on CentOS/RHEL/OEL 6.x

How to Upgrade from Solaris 10 to Solaris 11: Network Preparation