CANOGA PERKINS 2361 T1 Modem - Manual (Page 61)

The EdgeAccess Universal Chassis System
2361 Modem Users Manual 7-5
4. Use the Space Bar to toggle through each option (outlined below).
5. Use the Tab key to change redundancy options for Local and Remote, Primary and Secondary
Modems.
7.2.1 Redundancy Mode Options
Below is an explanation of each redundancy mode option. Note that when a redundant
configuration is detected and this screen is accessed, the program will automatically display
"Auto," defaulting to the automatic redundancy setting. If other redundancy modes are required,
access them through this screen's options.
Off: The two modems run independently. It is identical to a nonredundant
modem configuration, except that Redundant ELIMs are used.
Manual Primary: The data is delivered via the primary modem and will not switch
automatically to the secondary modem. However if failure is detected,
you can manually switch to the secondary modem.
Manual Secondary: The data is delivered via the secondary modem and will not switch
automatically to the primary. However if failure is detected, you can
manually switch to the primary modem.
Auto: Data is run across any active link in working order, primary or secondary.
If the system detects a fault, the data will switch. Possible data switch
causes would include:
• An ELIM or OLIM is removed
• Loss of Signal
• Modem Failure
• Composite error
• Modem reset
7.3 Important Definitions for Redundant Configurations
Primary Modem: The primary modem is active at boot time. When the redundant
configuration reboots, the primary modem will always carry the data
payload. If a problem is detected in the primary modem, the system will
switch over to the secondary modem. At this point, the secondary modem
is active, and the primary modem is inactive. In a rackmount modem, the
primary modem must be placed in an odd numbered slot, and the
secondary modem in the slot immediately to its right.
Secondary Modem: The secondary modem is inactive at boot time, but can become active
whenever an error is detected on the primary modem link. Data payload
will continue to transmit on the secondary modem until an error is
detected. It will then become inactive, and data payload will switch to the
primary modem. The term "secondary modem" is not synonymous with
"inactive modem." A secondary modem must be placed in an even slot
adjacent to the right of the primary modem of that same configuration. For
example, if the primary modem is placed in slot 3, the secondary modem
must be placed in slot 4.