Technical data

4. Packages
BONDING_DEV_x_PRIMARY Default: BONDING_DEV_x_PRIMARY=”
This setting is optional and can also be completely omitted.
Specify primary output device if mode is set to ’active-backup’. This is useful if the
various devices have different speeds. Provide a string (for example ’eth0’) for the device
to be used primarily. If a value is entered and the device is online it will be used as the
first output medium. Only if the device is offline another device will be used. If a failure
is detected a new standard output medium will be chosen. This comes in handy if one
slave has priority over another, for example if a slave is faster than another (1000 Mbit/s
versus 100 Mbit/s). If the 1000 Mbit/s slave fails and later gets back up it may be of
advantage to set the faster slave active again without having to cause a fail of the 100
Mbit/s slave artificially (for example by pulling the plug).
BONDING_DEV_x_ARP_INTERVAL Default: BONDING_DEV_x_ARP_INTERVAL=’0’
This setting is optional and can also be completely omitted.
The interval in which IP-addresses specified in BONDING_DEV_x_ARP_IP_TARGET_x are checked
by using their ARP responses (in milliseconds). If ARP monitoring is used in load-
balancing mode (mode 0 or 2) the switch should be adjusted to distribute packets to
all connections equally (for example round robin). If the switch is set to distribute the
packets according to the XOR method all responses of the ARP targets will arrive on
the same connection which could cause failure for all team members. ARP monitoring
should not be combined with miimon. Passing ’0’ will disable ARP monitoring.
BONDING_DEV_x_ARP_IP_TARGET_N Default: BONDING_DEV_x_ARP_IP_TARGET_N=”
This setting is optional and can also be completely omitted.
The number of IP-addresses which are used for ARP checking. A maximum of 16 IP-
addresses can be checked.
BONDING_DEV_x_ARP_IP_TARGET_x Default: BONDING_DEV_x_ARP_IP_TARGET_x=”
This setting is optional and can also be completely omitted.
If BONDING_DEV_x_ARP_INTERVAL is 0, specify one IP address which is used as the target
for ARP requests to evaluate the quality of the connection. Enter values using format
’ddd.ddd.ddd.ddd’. To get ARP monitoring to work at least one IP address has to be
given here.
4.2.3. VLAN - 802.1Q Support
Support for 802.1Q VLAN is reasonable only in conjunction with using appropriate switches.
Port-based VLAN switches are not suitable. A general introduction to the subject VLAN can
be found at http://en.wikipedia.org/wiki/IEEE_802.1Q. At http://de.wikipedia.org/wiki/
VLAN some additional information can be found.
Please note that not any network card can handle VLANs. Some can not handle VLANs at
all, others require a matching MTU and few cards work without any problems. The author of
the advanced_networking package uses Intel network cards with the ’e100’ driver without any
problem. MTU adjustment is not necessary. 3COM’s ’3c59x’ driver requires MTU adjustment
to 1496 otherwise the card won’t work correctly. The ’starfire’ driver does not work properly if
a VLAN device is added to a bridge. In this case no packets can be received. Those who want
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