MrPete
Occasional Visitor
Forum denizens -- can you fill in the answer for YOUR NAS on "Power Fail Management" based on the categories below? It would save me a lot of calling around and/or testing! If you can answer, please reply to this thread with NAS product and Power Fail Management category answer.
SmallNetBuilder folk -- any chance you would consider adding something like the "feature" evaluation described below to your NAS comparisons? This information has GOT to be valuable for more than me!
BACKGROUND
In updating our small biz (nonprofit) server situation, I've learned a painful lesson the hard way: many RAID boxes do not properly handle power outages. I've now been through several DAS units that all failed one way or another.
We're about to buy a high end NAS, and I'm having trouble finding the information I need. SmallNetBuilder does not include it in comparison tables, and only makes occasional hints about it. (A friend with a Thecus N7700 graciously tested his, so I know the answer for that one...)
The goal: lights-out computing for the SOHO/small business. If there's an extended power failure at the office, we shouldn't have to drive in (or return from vacation) to get things going again after wall power is restored.
With desktop computers and servers, this is not a big deal. Every one we've owned in recent years will restore power to its previous (on) state after a power failure. And even when controlled by a UPS (APC, etc), the same is true.
With DAS/NAS RAIDs, the situation is more murky.
[Note that having a UPS only delays the inevitable in the event of a power outage. 5 to 45 minutes after the lights go out, your equipment will lose wall power! We have some very nice UPS units... with two multi-hour power outages in the last month, the UPS's did their job but couldn't keep power on THAT long
]
POWER FAIL MANAGEMENT GRADES
Here are the levels of Power Fail Management I've seen over the years, and a suggested grade for each level.
ACCEPTABLE
"A" Auto-Power-Restore, with proper UPS monitoring: when wall power is restored, the unit correctly returns to the previous (on) power state. It monitors UPS battery, shuts down before UPS fails, and restores correctly to the "on" state when UPS/wall power is restored. [Thecus 7700 and others]
"B" Auto-Power-Restore, no UPS monitoring: when wall power is restored, the unit correctly returns to the previous (on) power state. It does not monitor UPS, which is potentially risky in case of power glitches.
"C" Dumb Mechanical Power Switch: if the mechanical power switch is on, the unit is on. It does not monitor UPS, nor shut down on timeouts. Dumb, and potentially risky in case of power glitches, but at least it works.
UNACCEPTABLE
"D-" Auto-Power-Restore except with UPS shutdown: These have proper restoration of previous power state, and even support UPS-controlled shutdown. But there's a bug: once power is restored, the DAS/NAS stays off until you fire it up.
"F" Manual eSwitch for Wall Power: after wall power is restored, you must push the electronic switch to restore power. [Sans Digital TS2CT DAS and others]
"F+" PC-Sync Wakeup with Manual eSwitch for Wall Power: These are advertised as powering on/off in sync with the attached system. What they don't tell you: that's actually only wakeup/sleep. The basic power on/off function is an eSwitch. As above, after wall power is restored, you must manually push the switch. [Mediasonic HFR2-S3B ProRAID DAS and others]
SmallNetBuilder folk -- any chance you would consider adding something like the "feature" evaluation described below to your NAS comparisons? This information has GOT to be valuable for more than me!
BACKGROUND
In updating our small biz (nonprofit) server situation, I've learned a painful lesson the hard way: many RAID boxes do not properly handle power outages. I've now been through several DAS units that all failed one way or another.
We're about to buy a high end NAS, and I'm having trouble finding the information I need. SmallNetBuilder does not include it in comparison tables, and only makes occasional hints about it. (A friend with a Thecus N7700 graciously tested his, so I know the answer for that one...)
The goal: lights-out computing for the SOHO/small business. If there's an extended power failure at the office, we shouldn't have to drive in (or return from vacation) to get things going again after wall power is restored.
With desktop computers and servers, this is not a big deal. Every one we've owned in recent years will restore power to its previous (on) state after a power failure. And even when controlled by a UPS (APC, etc), the same is true.
With DAS/NAS RAIDs, the situation is more murky.
[Note that having a UPS only delays the inevitable in the event of a power outage. 5 to 45 minutes after the lights go out, your equipment will lose wall power! We have some very nice UPS units... with two multi-hour power outages in the last month, the UPS's did their job but couldn't keep power on THAT long
]POWER FAIL MANAGEMENT GRADES
Here are the levels of Power Fail Management I've seen over the years, and a suggested grade for each level.
ACCEPTABLE
"A" Auto-Power-Restore, with proper UPS monitoring: when wall power is restored, the unit correctly returns to the previous (on) power state. It monitors UPS battery, shuts down before UPS fails, and restores correctly to the "on" state when UPS/wall power is restored. [Thecus 7700 and others]
"B" Auto-Power-Restore, no UPS monitoring: when wall power is restored, the unit correctly returns to the previous (on) power state. It does not monitor UPS, which is potentially risky in case of power glitches.
"C" Dumb Mechanical Power Switch: if the mechanical power switch is on, the unit is on. It does not monitor UPS, nor shut down on timeouts. Dumb, and potentially risky in case of power glitches, but at least it works.
UNACCEPTABLE
"D-" Auto-Power-Restore except with UPS shutdown: These have proper restoration of previous power state, and even support UPS-controlled shutdown. But there's a bug: once power is restored, the DAS/NAS stays off until you fire it up.
"F" Manual eSwitch for Wall Power: after wall power is restored, you must push the electronic switch to restore power. [Sans Digital TS2CT DAS and others]
"F+" PC-Sync Wakeup with Manual eSwitch for Wall Power: These are advertised as powering on/off in sync with the attached system. What they don't tell you: that's actually only wakeup/sleep. The basic power on/off function is an eSwitch. As above, after wall power is restored, you must manually push the switch. [Mediasonic HFR2-S3B ProRAID DAS and others]
