Power Monitoring
Last Modified: 12/18/2012 at 16:09 | Release:Table of Contents
Power Monitoring Options
Avance provides three ways to monitor power:
| No Monitoring | Default. Treats PM power supply loss the same as other predictive hardware faults. |
| Internal Monitoring | UPS model independent. Avance initiates a PM shutdown policy if it detects power loss for over 2 minutes. |
| External Monitoring | UPS model dependent. Vendor application executes shutdown policies via an Avance command line interface (CLI) script. |
To configure power monitoring:
- In the Avance Management Console, click Preferences. Click UPS.
- Select the power monitoring state from the menu.
Determining UPS Battery Requirements Minimum battery capacity in minutes depends on the memory allocated to VMs:
- 2 to cover short blackouts
- 3 to shutdown VMs
- 2 to shutdown PMs
- Time for VM migrations, equal to { total memory of all VMs (GB) } / 2
For example, VMs with 8GB memory require a UPS battery capacity of 2 + 3 + 2 + (8/2) = 11 minutes.
No Monitoring (Default)
When Avance detects that a PM has lost a redundant power supply, it immediately generates an alert and “live-migrates” VMs from that PM to its partner.
Internal Monitoring
Avance monitors the PM’s redundant power supplies and executes these policies on power loss:
- Power lost over 2 minutes on one PM: the VMs are live-migrated to the other PM, and then the affected PM is shut down.
- Power lost over 2 minutes on both PMs: the VMs are shutdown, and then both PMs are shutdown.
Shutdowns cannot be cancelled once begun. Internal monitoring requires redundant power supplies for each PM, with one supply connected to wall power and the other to a UPS:
| Single site, shared UPS configuration | Split site UPS configuration |
|---|---|
 |
 |
External Monitoring
External monitoring is used with a UPS power-management application such APC’s PowerChute Network Server (PCNS). These applications monitor the UPS for low battery and power loss, and can initiate shutdowns. For Avance, the application would execute a shutdown script containing Avance CLI (AVCLI) commands. The power-management application must be implemented in an external client. Avance does not support running a UPS agent directly in the Avance base layer. Avance takes no action when a PM loses power from a redundant supply in this situation, because the application executes the appropriate policy. Avance sends an e-Alert or SNMP trap if enabled, but does not send a call-home. The power-management application can also execute power-up sequences by controlling UPS outputs.
