Link Aggregation

Starting with firmware version Asuswrt-Merlin 3.0.0.4.374.33 bonding.ko Driver is included in the firmware.

There are several modes which should be possible.

1. balance-rr or 0
2. active-backup or 1
3. balance-xor or 2
4. broadcast or 3
5. 802.3ad or 4
6. balance-tlb or 5
7. balance-alb or 6

The only mode that has been tested is 802.3ad

NIC bonding in mode 802.3ad achieves 2 goals.

1. Increased Throughput
2. Failover Protection

But requires either a Switch/PC/NAS which also supports Link Aggregation.

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METHOD 1 - LINKAGG (Custom Script)

To Simplify setup and management a small shell script has been created.

Which can be downloaded

LinkAgg

Usage is as follows.

    ----  Link Aggregation Version 1.5 Help  ----
Dynamically enable Link Aggregation using 802.3ad
802.3ad requires a Switch/PC/NAS which...
also supports 802.3ad to function correctly
Usage: /path/to/LinkAgg <port> <port>
Example: /path/to/LinkAgg 3 4
Only 2 ports are currently supported
    --- Special Flags ---
Help: -h or --help
Status: -s or --status
Delete: -d or --delete
Version: -v or --version

To Make the Configuration persistent across reboots.

1. Enable JFFS partition
2. Edit /jffs/scripts/services-start to call the script at each boot

/Path/to/LinkAgg 3 4

Additional Notes.

Any additional configuration can be done manually in the services-start script

The Script above will use the sysfs driver because it does not require any additional packages.

Optionally users can choose to install entware - ifenslave package.

*** entware is for MIPS based routers only ***

More Info Here http://forums.smallnetbuilder.com/showthread.php?t=12735

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METHOD 2 - For AC68U/R/P Routers

Step 1 - NVRAM Edits | Note: You will need to repeat this step if you clear the nvram ie. Beta to Final versions, resetting to Factory default

Apply the following changes to the router's nvram:

nvram set vlan4ports="3 5t"
nvram set vlan5ports="4 5t"
nvram set vlan4hwname=et0
nvram set vlan5hwname=et0
nvram commit

Step 2 - Create/Edit services-start script

Include the following code in services-start script located in /jffs/scripts/ (you will need to create this file from scratch, if you haven't done so already, with the right permissions)

#!/bin/sh

# Logger Services
logger -t "($(basename ))" $$ SERVICES-START being started....

logger -t "($(basename ))" $$ Bonding ports 3 and 4 commencing....
# Pre-Bonding
robocfg vlan 1 ports "1 2 5*"

# Bonding
sleep 2s
modprobe bonding
# Setting mode to 802.3ad
echo 802.3ad > /sys/class/net/bond0/bonding/mode
# Setting LACP rate to fast
echo fast > /sys/class/net/bond0/bonding/lacp_rate
# Setting MII monitoring interval to 50
echo 50 > /sys/class/net/bond0/bonding/miimon
# Setting xmit hash policy to layer3+4
echo 1 > /sys/class/net/bond0/bonding/xmit_hash_policy
ip link set bond0 up
echo +vlan4 > /sys/class/net/bond0/bonding/slaves
echo +vlan5 > /sys/class/net/bond0/bonding/slaves
brctl addif br0 bond0

# Post-Bonding
sleep 2s
logger -t "($(basename $0))" $$ Bonding Status....
cat /proc/net/bonding/bond0 | sed 's/^/+++ /' | logger

Step 3 - Create/Edit firewall-start script

Include the following code in firewall-start script located in /jffs/scripts/ (you will need to create this file from scratch, if you haven't done so already, with the right permissions)

#!/bin/sh

# Bonding IPtables rules
iptables -I INPUT -i vlan4 -j ACCEPT
iptables -I INPUT -i vlan5 -j ACCEPT
iptables -I INPUT -i bond0 -j ACCEPT

Firewall/IPtables Performance Tweak for Bond0 to be placed right after the above bonding rules and before your custom rules - if any.

iptables -D INPUT iptables --line-numbers -nL INPUT | grep ESTABLISHED | tail -n1 | awk '{print $1}' iptables -I INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

Step 4 - Set the switch's LAG hashing mode

This is the LAG config profile you created for the 2 switch ports you have assigned to the router's port 3 and 4.

Set the hashing mode to "Source/Destination MAC, VLAN, EtherType, source MODID/port" or the equivalent mode in your switch.

Step 5 - Reboot

Additional Notes.

This method may be adapted to work with other Asus routers. Hint: Internal switch port mappings.

More info Here http://forums.smallnetbuilder.com/showthread.php?t=20441