Link aggregation combines (aggregates) multiple network connections in parallel, in order to increase throughput and to provide redundancy in case one of the links fails.

Bonding Interface Settings

The following settings are available to configure the bonding interface:

slave <iface> <iface>...

interfaces to add in the bonding

bonding primary <iface>

primary slave for current bond

bonding mode <mode>

bonding mode (default: 1 or active-backup)

bonding updelay <ms>

bonding delay check in ms (default: 1000)

bonding downdelay <ms>

bonding delay check in ms (default: 1000)

Note

When a physical interface is part of a bond, it cannot have an IP configuration.

To create a link aggregation, you have to create a new service network.

Create a new service network

  1. Browse the ALOHA WUI.

  2. Open the Services tab.

  3. Click Setup setup_icon on the Network line.

  4. Add a directive to create a new bonding interface: service network bond<bondid>

service network bond0

Aggregation modes

The ALOHA allows the following bonding mode:

0 or balance-rr

Output interfaces are chosen using a round robin method.

1 or active-backup mode

Failover mode with one active interface at a time.

2 or balance-xor mode

Transmit based on [(source MAC address XOR'd with destination MAC address) modulo slave count]. This selects the same slave for each destination MAC address. This mode provides load balancing and fault tolerance and does not require any configuration on the switch.

4 or 802.3ad

IEEE 802.3ad (LACP) Dynamic link aggregation. The switch must be compatible and properly configured.

5 or balance-tlb

Transmit load-balancing; outgoing interface is chosen based on interfaces load.

6 or balance-alb

Adaptive load-balancing; balance-tlb mode with a reception load-balancing mode made using ARP protocol.

Active/passive modes

Set active/passive mode

  1. Browse the ALOHA WUI.

  2. Open the Services tab.

  3. Click Setup setup_icon on the Network line.

  4. Edit the entire network configuration directive:

    • remove any IP configuration from the slave interfaces

    • create / update a bond interface

    Create a bond0 interface in active / passive mode on top of eth0 and eth1:

    service network eth0
 auto on
service network eth1
 auto on
service network bond0
 slave eth0 eth1
 bonding primary eth0
 bonding mode active-backup
 ip address 192.168.1.10/24
 ip route default 192.168.1.1

  5. Click ok .

  6. Click close .

  7. Apply the configuration:

    • If you just created the bond interface, click Restart restart_icon on the network line.

    • If you just updated an existing bond interface, click Reload reload_icon.

In case of problem, refer to the section on troubleshooting bond interfaces.

Note

We recommend that you read and consider applying the section about xmit-hash-policy.

LACP / 802.3ad

Link Aggregation Control Protoco (LACP) is part of the IEEE specification 802.3ad that allows you to bundle several physical ports to form a single logical channel.

In this mode, the switch ports where the ALOHA's interfaces are plugged in must also be configured in LACP.

Configure LACP

  1. Browse the ALOHA WUI.

  2. Open the Services tab.

  3. Click Setup setup_icon on the Network line.

  4. Edit the entire network configuration directive:

    • Remove any IP configuration from the slave interfaces

    • Create / update a bond interface

    Create a bond0 interface in active / passive mode on top of eth0 and eth1:

    service network eth2
 auto on
service network eth3
 auto on
service network bond1
 slave eth2 eth3
 bonding primary eth2
 bonding mode 802.3ad
 ip address 192.168.1.10/24
 ip route default 192.168.1.1

  5. Apply the configuration:

    • If you just created the bond interface, click Restart restart_icon on the network line.

    • If you just updated an existing bond interface, click Reload reload_icon.

In case of problem, refer to the section on troubleshooting bond interfaces.

Note

We recommend that you read and consider applying the section about xmit-hash-policy.

Advanced parameter: xmit-hash-policy

When used in active/active mode (i. e. LACP), the choice of the outbound network interface is made using the destination MAC address.

Unfortunately, this is not enough in some cases: for example when the traffic to your default gateway is higher than a single network interface capacity.

In such cases, it is possible to change the xmit-hash-policy by setting the /sys parameter.

Set the xmit-hash-policy

  1. Browse the ALOHA WUI.

  2. Open the Services tab.

  3. Click Setup setup_icon on the bonding interface you want to configure.

  4. Add a xmit-hash-policy directive using the syntax below:

    bonding xmit_hash_policy <policyid>

The <policyid> can have two values and describes the information used to compute the hash algorithm:

0 or layer2

Use the destination MAC address

1 or layer3+4

When available, use source and destination IPs and ports

Change xmit_hash_policy to 1 for bond1:

service network bond1
 slave eth2 eth3
 bonding primary eth2
 bonding mode 802.3ad
 ip address 192.168.1.10/24
 ip route default 192.168.1.1
 bonding xmit_hash_policy 1

Troubleshooting bond interfaces

Check the Network Interface Troubleshooting guide and validate the following statements.

When the bonding configuration is correctly set up:

  • The bondX interface has at least the MASTER and MULTICAST labels

  • The ethX interfaces have at least the SLAVE and MULTICAST labels

  • Both bondX and associated ethX are UP

  • The bondX and ethX interfaces have the same MAC address

Example output

bond0 Link encap:Ethernet HWaddr 00:0D:B9:13:52:2D
   inet addr:10.0.32.10 Bcast:0.0.0.0 Mask:255.255.0.0
   UP BROADCAST RUNNING MASTER MULTICAST MTU:1500 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)
eth0 Link encap:Ethernet HWaddr 00:0D:B9:13:52:2D
   UP BROADCAST NOARP SLAVE MULTICAST MTU:1500 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:1000
   RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
   Interrupt:11 Base address:0x2000
eth1 Link encap:Ethernet HWaddr 00:0D:B9:13:52:2D
   UP BROADCAST NOARP SLAVE MULTICAST MTU:1500 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:1000
   RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
   Interrupt:12 Base address:0x4000