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Configuration
Configuring the High Availability Feature for X.25 over LLC2
WARNING
Configuring the High Availability Feature for X.25 over LLC2
This section describes configuring the local and remote failover features for X.25 over LLC2 (XOL) interface. It also describes the local, remote, and combination of local and remote failover. XOL is not supported over APA (Auto Port Aggregation).
The failover is not transparent and results in loss of data and existing connections. After a failover, the XOL connections must be
NOTE
NOTE
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Unique MAC Address Requirement
XOL High Availability (XOL HA) is based on sharing a unique MAC address for the primary and standby LAN cards, whichever is active. The use of a unique MAC address makes the card swap transparent from the XOL router side or peer system, which sees the same MAC address associated with the active interface.
To avoid MAC address collision, the system administrator must identify an unused, unique MAC address in their LAN subnet. The lanadmin command is used to change the MAC address of the card. After failover, the failed LAN card is reconfigured with its factory default MAC address.
Before you run the lanadmin command to set up the unique MAC address, you may test whether the MAC address chosen by you is selected by running the linkloop command. For more information, see linkloop (1m). The uniqueness of the MAC address is verified on the LAN cards currently active in the LAN segment. The linkloop command sends an OK message if the MAC address is already in use.
The routing table of the router connected to the host system must be updated with the unique MAC address identified by the user. If the XOL router supports the Hunt Group facility for XOL HA, the unique MAC
Chapter 3