Describes how Cisco 8800 Modular Routers transfer redundant power supply units to the power reservation pool on demand to meet component requirements.
The on-demand transfer of redundant power modules to power reservation pool is a power management process that
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prioritizes component power requirements over redundancy preservation
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transfers redundant power modules to the power reservation pool on demand, and
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restores redundancy automatically when power consumption decreases.
| Feature Name |
Release Information |
Feature Description |
|---|---|---|
| On-demand transfer of Redundant Power Modules to Power Reservation Pool |
Release 25.4.1 |
Introduced in this release on: Fixed Systems (8010 [ASIC: A100])(select variants only*) *This feature is supported on:
|
| On-demand transfer of Redundant Power Modules to Power Reservation Pool |
Release 25.1.1 |
Introduced in this release on: Fixed Systems (8700 [ASIC: K100], 8010 [ASIC: A100])(select variants only*) *This feature is supported on:
|
| On-demand transfer of Redundant Power Modules to Power Reservation Pool |
Release 24.4.1 |
Introduced in this release on: Fixed Systems (8200 [ASIC: P100], 8700 [ASIC: P100])(select variants only*); Modular Systems (8800 [LC ASIC: P100])(select variants only*) *This feature is now supported on:
|
| On-demand transfer of Redundant Power Modules to Power Reservation Pool |
Release 7.11.1 |
The Cisco 8800 Series Modular Routers now have a functionality that allows them to transfer their redundant Power Supply Units (PSUs) to the power reservation pool when there is inadequate power supply. This capability helps prevent the router from shutting down hardware components due to a lack of power in the reservation pool, which used to occur due to the router prioritizing redundancy over power availability in the power reservation pool. Consequently, the router now raises an alarm indicating redundancy loss when it transfers PSUs to the power reservation pool. This feature ensures that the router components reserve the necessary power, even when redundancy is enabled. |
Cisco 8000 Series Modular Routers provide redundancy while managing Power Supply Units (PSUs) to ensure continuous operation. By default, the router operates in N+1 redundancy, where N represents the number of PSUs allotted to the power reservation pool and 1 indicates the backup PSU. Administrators configure the PSU redundancy from N+1 to N+x using the power-mgmt redundancy-num-pms command, where x represents the number of redundant PSUs. The system requires that the total number of functioning PSUs remains at least x more than the number of PSUs required to support the power demanded by all system components.
The Cisco 8000 Series Modular Routers offer redundancy while managing Power Supply Units (PSUs), providing continuous operation if there is PSU failure. By default, the router operates in N+1 redundancy, where N represents the number of PSUs allotted to the power reservation pool for powering the router components, and 1 indicates the backup PSU. You can use the power-mgmt redundancy-num-pms number command in the XR config mode to configure the PSU redundancy from N+1 to N+x, where x is the number of redundant PSUs required. The total number of functioning PSUs must be at least x more than the number of PSUs required to support the power demanded by all the components in the system for optimal router functionality. The range of values assigned to x is 0–11, where 0 implies no power redundancy. The router uses the redundant PSUs only when there is a PSU failure. But, if the power requirement of the router increases than the available power offered by PSUs, the router prioritizes maintaining PSU redundancy overpowering the components.
Cisco 8800 Modular Routers prioritize powering router components over maintaining redundancy. When the power requirement exceeds the available power in the reservation pool, the router transfers redundant PSUs to the power reservation pool to meet demand. The system automatically restores redundancy and clears the associated alarm if subsequent actions reduce power consumption.
For example, consider a scenario with 18900W (3 6300W PSUs) available power. Initially, the router reserves 12600W (using 2 PSUs) in the power reservation pool and retains 6300W (one PSU) as a backup to maintain N+1 redundancy. Suppose the router needs to reserve power for any components to power up and needs more power than is available in the reservation pool. In that case, the router uses the entire 18900W with all three PSUs to power the components by transferring the redundant PSU to the power reservation pool. The router then triggers a redundancy loss alarm with such an assignment. However, if any further actions result in reduced power consumption in the router, the system automatically restores redundancy and clears the redundancy lost alarm.
The router provides the following monitoring and verification capabilities:
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On redundancy loss, the router raises a Critical severity Power Module redundancy lost alarm. You can use the show alarms brief command to view the redundancy lost alarm.
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Syslog message created while redundancy loss (transforming redundant PSU to functional PSU):
RP/0/RP0/CPU0:Jul 24 11:49:01.316 UTC: envmon[214]: %PKT_INFRA-FM-3-FAULT_MAJOR : ALARM_MAJOR :Power Module redundancy lost :DECLARE :0: -
Syslog message created while restoring redundancy:
RP/0/RP0/CPU0:Jul 24 11:49:11.375 UTC: envmon[214]: %PKT_INFRA-FM-3-FAULT_MAJOR : ALARM_MAJOR :Power Module redundancy lost :CLEAR :0: -
Use the show environment view the redundancy status of the PSUs in the router.
Verify the redundancy status in the router
This section details the commands to verify the redundancy status in the router:
Router with N+1 redundancy:
Router:ios# show environment power
================================================================================
CHASSIS LEVEL POWER INFO: 0
================================================================================
Total output power capacity (N + 1) : 12600W + 6300W
Total output power required : 11545W
Total power input : 3302W
Total power output : 3004W
================================================================================
Power Supply -------Input-------- -----Output--- Status
Module Type Volts A/B Amps A/B Volts Amps
================================================================================
0/PT5-PM0 PSU6.3KW-HV 240.5/241.3 2.2/2.4 55.1 18.3 OK
0/PT5-PM1 PSU6.3KW-HV 240.5/240.8 2.1/2.3 54.8 17.3 OK
0/PT5-PM2 PSU6.3KW-HV 242.2/241.1 2.3/2.4 54.9 19.1 OK
Total of Power Modules: 3302W/13.7A 3004W/54.7A
================================================================================
Location Card Type Power Power Status
Allocated Used
Watts Watts
================================================================================
0/RP0/CPU0 8800-RP 105 78 ON
0/RP1/CPU0 - 105 - RESERVED
0/0/CPU0 8800-LC-36FH 1097 513 ON
0/1/CPU0 - 102 - RESERVED
0/2/CPU0 88-LC0-36FH 102 0 OFF
0/3/CPU0 - 102 - RESERVED
0/4/CPU0 - 102 - RESERVED
0/5/CPU0 - 102 - RESERVED
0/6/CPU0 - 102 - RESERVED
0/7/CPU0 - 102 - RESERVED
0/8/CPU0 - 102 - RESERVED
0/9/CPU0 - 102 - RESERVED
0/10/CPU0 - 102 - RESERVED
0/11/CPU0 - 102 - RESERVED
0/12/CPU0 - 102 - RESERVED
0/13/CPU0 - 102 - RESERVED
0/14/CPU0 - 102 - RESERVED
0/15/CPU0 - 102 - RESERVED
0/16/CPU0 - 102 - RESERVED
0/17/CPU0 - 102 - RESERVED
0/FC0 - 32 - RESERVED
0/FC1 - 32 - RESERVED
0/FC2 8818-FC0 584 475 ON
0/FC3 - 32 - RESERVED
0/FC4 8818-FC0 584 472 ON
0/FC5 - 32 - RESERVED
0/FC6 - 32 - RESERVED
0/FC7 - 32 - RESERVED
0/FT0 8818-FAN 1786 237 ON
0/FT1 8818-FAN 1786 228 ON
0/FT2 8818-FAN 1786 234 ON
0/FT3 8818-FAN 1786 228 ONRouter with redundancy loss:
Router:ios# sh env power
================================================================================
CHASSIS LEVEL POWER INFO: 0
================================================================================
Total output power capacity (N + 1) : 18900W + 0W
Total output power required : 12689W
Total power input : 3302W
Total power output : 3004W
================================================================================
Power Supply -------Input-------- -----Output--- Status
Module Type Volts A/B Amps A/B Volts Amps
================================================================================
0/PT5-PM0 PSU6.3KW-HV 240.5/241.3 2.2/2.4 55.1 18.3 OK
0/PT5-PM1 PSU6.3KW-HV 240.5/240.8 2.1/2.3 54.8 17.3 OK
0/PT5-PM2 PSU6.3KW-HV 242.2/241.1 2.3/2.4 54.9 19.1 OK
Total of Power Modules: 3302W/13.7A 3004W/54.7A
================================================================================
Location Card Type Power Power Status
Allocated Used
Watts Watts
================================================================================
0/RP0/CPU0 8800-RP 105 78 ON
0/RP1/CPU0 - 105 - RESERVED
0/0/CPU0 8800-LC-36FH 1097 513 ON
0/1/CPU0 - 102 - RESERVED
0/2/CPU0 88-LC0-36FH 916 510 ON
0/3/CPU0 - 102 - RESERVED
0/4/CPU0 - 102 - RESERVED
0/5/CPU0 - 102 - RESERVED
0/6/CPU0 - 102 - RESERVED
0/7/CPU0 - 102 - RESERVED
0/8/CPU0 - 102 - RESERVED
0/9/CPU0 - 102 - RESERVED
0/10/CPU0 - 102 - RESERVED
0/11/CPU0 - 102 - RESERVED
0/12/CPU0 - 102 - RESERVED
0/13/CPU0 - 102 - RESERVED
0/14/CPU0 - 102 - RESERVED
0/15/CPU0 - 102 - RESERVED
0/16/CPU0 - 102 - RESERVED
0/17/CPU0 - 102 - RESERVED
0/FC0 - 32 - RESERVED
0/FC1 - 32 - RESERVED
0/FC2 8818-FC0 749 475 ON
0/FC3 - 32 - RESERVED
0/FC4 8818-FC0 749 472 ON
0/FC5 - 32 - RESERVED
0/FC6 - 32 - RESERVED
0/FC7 - 32 - RESERVED
0/FT0 8818-FAN 1786 237 ON
0/FT1 8818-FAN 1786 225 ON
0/FT2 8818-FAN 1786 234 ON
0/FT3 8818-FAN 1786 228 ONRouter:ios# sh alarms brief system active
------------------------------------------------------------------------------------
Active Alarms
------------------------------------------------------------------------------------
Location Severity Group Set Time Description
------------------------------------------------------------------------------------
0/RP0/CPU0 Critical Software 10/27/2023 00:22:08 UTC Redundancy Partner Not Present
0 Major Environ 10/27/2023 00:23:48 UTC Power Module redundancy lost
0/RP0/CPU0 Minor Fabric 10/27/2023 00:22:39 UTC Fabric Plane-0 status
0/RP0/CPU0 Minor Fabric 10/27/2023 00:22:39 UTC Fabric Plane-1 status
0/RP0/CPU0 Minor Fabric 10/27/2023 00:22:39 UTC Fabric Plane-3 status
0/RP0/CPU0 Minor Fabric 10/27/2023 00:22:39 UTC Fabric Plane-5 status
0/RP0/CPU0 Minor Fabric 10/27/2023 00:22:39 UTC Fabric Plane-6 status
0/RP0/CPU0 Minor Fabric 10/27/2023 00:22:39 UTC Fabric Plane-7 status
0/RP0/CPU0 Major Software 10/27/2023 00:22:59 UTC Communications Failure With Cisco Licensing Cloud
0 Major Environ 10/27/2023 00:23:48 UTC Power Module redundancy lost