Applies To:

Show Versions Show Versions

Manual Chapter: Introduction to All-Active Clustering using ECMP
Manual Chapter
Table of Contents   |   Next Chapter >>

Overview: Configuring all-active clustering using ECMP

You can implement the clustering of BIG-IP devices on a network through the use of the Equal Cost Multi-Path (ECMP) protocol. Specifically, you can enable ECMP on an upstream router and then configure the same virtual IP address on each BIG-IP device in a Sync-Only device group. In this case, the upstream router uses ECMP to determine, through route advertisement, whether there are multiple, equal-cost paths to the virtual address. If so, the router employs an algorithm to select a path to the virtual address on any one of the BIG-IP devices.

With this configuration, no single application is pinned to a specific device, and no device operates in a standby state. Instead, all devices in the cluster can be active for that application traffic. Moreover, you can add capacity by simply adding BIG-IP devices to the device group and syncing the configuration, including the virtual IP address, to the new device. Note that all devices in the Sync-Only device group function as standalone devices and therefore do not share state, such as mirroring connections, persisting records, and so on.

You can configure all-active BIG-IP clustering in these ways:

Configuring the virtual server to use SNAT Auto Map

In the configuration example provided in this document, the pool members are on the internal network of the BIG-IP systems. However, because SNAT Auto Map selects the unique self IP address that is local to a device, the pool members can actually reside anywhere on the network, as long as they have a route back to those unique local self IP addresses.

Configuring the virtual server to use SNAT pools

  • SNAT pools can provide segmentation of traffic per application, as well scale the amount of connections per pool member.
  • In the configuration example provided in this document, the pool members are remote and located on the ECMP router's internal network. The virtual server leverages an iRule to select a unique SNAT pool for each device.
  • Because the SNAT pool addresses in this configuration are shared across all devices in the BIG-IP device group, the SNAT addresses must be routable only (that is, not on a directly-connected network).
  • All instances reference the same iRule, which selects the SNAT pool for each device. In this case, the server pool is on the ECMP router's internal network.
Important: These configuration solutions make use of the administrative partitioning feature of the BIG-IP system. As you implement this configuration, it is essential that you create each BIG-IP object in the appropriate partition, as indicated within each object's configuration task.
Table of Contents   |   Next Chapter >>

Was this resource helpful in solving your issue?

NOTE: Please do not provide personal information.

Additional Comments (optional)