PDU recommendations

We currently use Triplite stuff but they've got an issue where after a few
minutes, they stop accepting new tcp connections. We're adding a new 30A
circuit and I'm thinking of going with APC (ran them in the past and never
had any issues). However, I figured I'd see if there was a better brand /
specific model recommendations for quality or bang / buck?

Specs: 30A 24+ port 0U, managed (with ssh), lcd use display.


I'd go with APC it's quite monitorable and most NMS packages including Zenoss (where I work) have extensions to monitor it. There's a half dozen open source ZenPacks for APC including UPS's and PDU's.


Personally have gotten sick of dealing with basically every other
vendors PDU out there but APC. APC PDUs may not have every whiz-bang
feature but they work. SNMP or SSH pretty solid. You still probably
want them on a closed management network but problems even in the wild
'net with port 22 open in my experience have been rare. Management
software upgrades are generally live, load left on/undisturbed. I
still schedule them for downtime but (knock on wood) nothing in the
last 6-7 years has caused an outage.

Hello Michael, does that mean you do not employ PDUs in your network?
I.e., found a UPS with sufficient number of outlets in the back. With
that in mind, could you make a recommendation for such a UPS-direct
for a VM environment.

Kind Regards,


No, I only use APC anymore for PDUs. It's the others I've dealt with
I don't like. There's quite a few I've never used but after the
painfully expensive experiences I've had with Tripp-Lite, Bay tech,
MGE (though I think they're part of Schneider or APC now), Liebert
(which at the time looked suspiciously the same as the Tripp-Lite's
but with a bigger price tag), and a couple others I'm certainly

I'd heard there were some bad batches that were DOA from APC, but
haven't personally experienced any myself. I've had a couple
management cards in Symmetra LXes fail, and that same Symmetra chassis
had a power/inverter/charger module fail around the same time.

Raritan has a good line, the usual features, we use a lot of 2U, 208v,30A units with 20xc13 which is a good config these days

Their central management software, while not perfect, is excellent for pdu control

Been at a place where they have hundreds of APC's in production, all monitored and reporting back. Hardly a lick of trouble.
Love the fact you can reboot the management interface in the rare case there is a hang and it does not affect the status of the outlets.

And now for the stupid question. Is there an APC UPS in a U form factor
with sufficient
outlets that can act kind of like a PDU, only better?

PS If it has stonith capabilities ever better!!!

Kind Regards,


I'll also throw out recommendations for ServTech PDUs. They have an affordable line of PDUs with static transfer switches that are particularly attractive for all your single-power-supply devices.

Nick, he meant he was using APC PDUs, not APC UPSs with PDU functionality...

APC is also the PDU vendor I would recommend.

I used an APC (I think) 1U PDU at a client a few years back. The bugger was it wasn't deep, so after the cabinet started getting really populated, the back outlets were a PITA. We started using the full-height back of the cabinet PDU strips (one on each side for A & B power respectively) after that SNAFU.


I also have had good experience with (used) servertech/century/power tower (I think all the same brand) - very inexpensive; if you are in santa clara I have some spare 2u 16 port 208v (20a/c19) units.

Here is something a buddy wrote up when we were wiring them to the user-accessable power on/off menu:


My new rack is all avocent PM3001-401 units. Used, of course; but the feature I was after was per-port power monitoring.

I haven't quite gotten 'em all the way figured out yet. One thing I see as a negative (but might be positive?) is that they have fuses, not breakers. I don't know if this provides better protection; I do know that when my buddy overloaded one of them in testing, I had to replace fuses, rather than just switching a breaker back. (also, when a different buddy plugged a ancient desktop (so old the PSU wasn't auto-switch) with the power input switch set to 110 in, it blew some of the fuses in the PDU (and took out the rack) - it didn't damage any of the other servers on the pdu (other than taking out the PDU; but everything came back up when I swapped it with my spare.)

Also note, uh, the servertech and the avocent and I think all the other PDUs I've seen can reboot the management interface without flipping the outlets. I did it a bunch when I was getting familiar with the avocent.

Yeah. I think I need to give fewer buddies access to production.

Nobody takes hardware seriously enough. I can find people I trust with root, and that trust doesn't seem misplaced. But I let them touch the hardware? and they fuck it up. So I end up doing almost all the hardware stuff myself.

So, that's not a very good endorsement :slight_smile:

Idk why you'd use a fuse in a PDU.

The management interface can be rebooted without taking anything down on
the TrippLite but it's at a colo and it *shouldn't* time out like it does.
I think of this like a vehicle computer - if it goes down, you might still
drive for a little but get ready for a crash.

So, that's not a very good endorsement :slight_smile:

Idk why you'd use a fuse in a PDU.

MCB units age. Especially with vibration. A 10A MCB becomes a 9A MCB after some miles.

Fuses don't.

MCB units are good at protecting people since they trip quickly and aggressively.

Fuses tend to linger before blowing, and thus are comparatively bad at protecting
people (longer shock) but better at protecting infrastructure (surge
and switch-on-transient resistance).

Does anyone on list have experience with the APC AP7920 switched rack PDU, or any of the horizontal rack mountables with management? We're looking at these for our remote sites.

We seem to always get calls from uplogix.. Check them out if you are considering managing pdu's etc. Their gear is pretty stout, and they have good to great support.



    They are good.

    Nothing I would deploy in a large data center but for a few racks
they are perfect.

    Beware that they are not built to be connected straight to the
internet =D.

    The management module can reset depending on packet payload and
overall traffic. They should always be behind some sort of firewall
with rules limiting its access.

    PS: Ours are a few years old, I'm sure APC added some sort of
security since then, you may want to look 'em up.

    Happy 24th to all.

Heh, I wouldn't dream of putting this type of device on the net - nothing
good can come from that.

Oh, absolutely. These would be secured on a separate, private network with very specific access controls.

These remote sites are more "branch" than data center. Looking at a very limited amount of equipment (1-2 open telco racks/site).

APC's are what I've grown to love... mostly because they're cheap and plentiful (eBay!) The only issue I've had with them is "flash corruption"; sometimes they have to be reprogrammed after a power outage. I'm using metered PDUs so it never effects the servers.

But I also have a set of ServerTech dual-feed units. The full monty of DC features. (in fact, what a number of colo providers use.) I've not used them in years, 'tho -- lack of facilities to power them. (the electrician got a little happy cutting out old wiring in the current office and killed the two existing L6-30 drops. everything else is L21-20.)