Comtech EF Data LPOD Installation And Operation Manual page 146

LPOD Outdoor Amplifier / Block Up Converter (BUC)
Appendix A
The LPOD redundant mode does not specify which unit must be the backup (offline) unit.
Instead, the status of the backup (offline) and active (online) units are determined by the
waveguide switch position. The advantage to using this redundant method is that, after a failure
is detected and the backup unit causes a redundant switchover to occur, the failed unit can be
replaced without forcing a second switchover to occur. This is because the backup unit becomes
the active unit, and when another unit is installed in the system it automatically becomes the
new backup unit.
Redundant mode allows the backup (offline) unit to take control of the redundant system and
force a redundant switchover when there is a problem with the active (online) unit. Currently,
1:1 redundancy is supported with either transmit switching or transmit and receive switching.
The backup unit controls the waveguide switches and polls the active unit through the inter-unit
redundant link, so that it will be ready to take over for the active unit if necessary.
Because the inter-unit redundant link uses the RS-232 interface to communicate, the user
remote commands to the redundant system must instead be sent through one of the other
remote communications interfaces (i.e., RS-485, Telnet, HTTP, or SNMP). The inter-unit
redundant link is not used when the units are in manual redundant mode or when they are in
standalone (redundancy disabled).
The following parameters are updated via the inter-unit redundant link (the equivalent remote
command is shown in parentheses):
• Auto Fault Recovery (AFR)
• Amplifier state (AMP)
• Attenuation (ATT)
• Auxiliary Mute (AUX)
• LNB Current Window Enable (CWE)
*Date (DAY)
•
• Enable Statistics Averaging (ESA)
• Enable Statistics Logging (ESL)
• LNB Current Source enable (LCS)
• LNB Current Window (LCW)
*Note: Date and Time are only updated when the inter-unit redundant link is either established
or re-established.
The online status of a unit in a redundant system is determined by the position of the Tx
waveguide switch. When the Tx waveguide switch is oriented to allow a unit to send RF power
to the antenna (as determined by the waveguide switch failsafe indicator), the unit is considered
to be online. Otherwise, the unit is considered to be offline.
When redundant mode is disabled, the unit will always report that it is online. This is because
standalone mode does not use the Tx waveguide switch position to determine online status,
• Low Power Threshold (LPT)
• Local / Remote Setting (LRS)
• User fault mask (MSK)
• RF mute (MUT)
• Offline Mute (OFM)
• Remote LNB Control (RLC)
• Set Baud Rate (SBR)
• Set Statistics Interval (SSI)
*Time (TIM)
•
• External Reference Mute (XRM)
A–2
Revision 9
MN-LPOD