HP J3188A manual T e G g e s t i o n, Hub can monitor only one link

Backup Links

Examples of Backup Links

Backup Links

N o t e

S u g g e s t i o n

When the primary link is repaired, you must re-enable the primary port. It is not re-enabled automatically. When the primary port is enabled, the backup port is automatically disabled and returned to backup mode. See “Reactivating the Primary Link” later in this appendix.

■Any combination of media types can be used as a backup link by attaching an external transceiver to the AUI port. This port accepts fiber, thin coax, twisted-pair external transceivers. For example, a thin coax link from the ThinLAN port can act as a backup link to a twisted-pair link.

■The hub can monitor only one link.

■The remote device should have no more than 2 backup links connected to it from a monitoring hub. If the remote device has more than 2 backup links functioning, it may not be able to respond to the test packets fast enough when there is a high level of data traffic on the network segments.

■This ability to respond may be improved by increasing the time between test packet transmissions on the monitoring hubs. For all the backup links in which the remote device is involved, the time configured on the monitoring hubs for those links should be increased by one second for each additional backup link beyond two links. Add one to this count if the remote device is also functioning as a primary (monitoring) hub for a different link.

The primary link and the backup link cabling should be run over different paths (through different conduits, for example) to reduce the possibility that damage will occur to both cables simultaneously.

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