AP7900 configuration file gibberish

[Terry_Kennedy_apc]

This was originally posted on APC forums on 8/9/2017

---

I was wondering if someone could give me some info about the HW02 management in the AP7900. I have a unit that started reporting an "A!" application failure. The configuration file is being corrupted in various places. For example:

[RackPDULoad]
OverloadAlarmThreshold1=12 Amps
NearOverloadAlarmh2e3h/l$1=8 A-p3
L/wo!da2n)n'T(r%s(o,d1=0 
m0s
v%r,o!du4letRestriction1=None

I re-flashed the AOS and APP (392/392) and did a "clear configuration" from the console serial port and neither helped. I have 3 questions (I realize that this is unsupported - I'd just appreciate whatever information people are willing to provide - and if the answers are better given by private message, that's fine too).

1) I believe that "clear configuration" just does a line-at-a-time set to the default value, not a complete wipe of the configuration, so there is no way to really erase the whole configuration. Is there a way to do that that I've missed? Possibly in my third question?

2) There is a battery on the HW02 card stack in the unit (for other people - this is past a "warranty void if removed" sticker, so you don't want to try this yourself). My recollection is that this battery just maintains the real-time clock when the unit is un-powered, and that it has no part in retaining the configuration memory. Is that correct?

3) I have some other HW02 card stacks (out of AP775x ATS that suffered relay weld) and can swap the whole management hardware with one of those. Obviously, I'll get an "incorrect app" error, but that should be fixable by uploading the correct app, correct? The card will still report it is an AP775x and not an AP790x. I could either ignore that or reconfigure it. The easiest way would be to update the vital product data in the EEPROM. On an older unit, I would use 10man to edit the EEPROM. On these units, with modern software, 10man doesn't work (hard reset by holding the reset button down until the link status LED stops flashing, then trying 10man). The 10man is still in the product, I just don't know how to get to it. Is anyone willing to give me a hint (probably via PM)? 

Thanks in advance for any advice.

[voidstar_apc · Accepted solution]

This was originally posted on APC forums on 8/10/2017

---

On 8/9/2017 10:11 PM, Terry said:

1) I believe that "clear configuration" just does a line-at-a-time set to the default value, not a complete wipe of the configuration, so there is no way to really erase the whole configuration. Is there a way to do that that I've missed? Possibly in my third question?

I'm not familiar with the AP7900 specifically, but my understanding is doing "Reset to Defaults" from the console menu on a 3xx / HW02 card erases everything by reformatting the filesystem. You can also force stuff to get reinitialized by loading in a different app. It's also possible that there's configuration data on the mainboard of the device.

On 8/9/2017 10:11 PM, Terry said:

2) There is a battery on the HW02 card stack in the unit [...] this battery just maintains the real-time clock when the unit is un-powered, and that it has no part in retaining the configuration memory. Is that correct?

Correct. It's possible the RTC stores some memory, but I doubt it would have anything to do with your problem.

On 8/9/2017 10:11 PM, Terry said:

3) I have some other HW02 card stacks (out of AP775x ATS that suffered relay weld) and can swap the whole management hardware with one of those. Obviously, I'll get an "incorrect app" error, but that should be fixable by uploading the correct app, correct?

Yup.

On 8/9/2017 10:11 PM, Terry said:

 The card will still report it is an AP775x and not an AP790x.

That's a problem. If you find a way to edit the eeprom, I'd be interested in what you find.

[Terry_Kennedy_apc]

This was originally posted on APC forums on 8/15/2017

---

I loaded the Symmetra app and that cleared the config. Re-loading the RPDU app gave me a clean config and a good 7 segment display and relay control. Thanks for the suggestion!

Doing a "reset to defaults" didn't do it - I had tried that previously. Based on the log messages, it was setting things one line at a time (makes sense, if the "reset to defaults except TCP/IP" does the same thing).

I'm pretty sure the relay board doesn't have any sort of fancy microcontroller on it. And the input / current transformer board definitely doesn't. It was interesting to see that those two boards are apparently identical across many RPDU models - the relay board has a daisy-chain connector and the current transformer board is actually stuffed with parts for all 3 phases.

My fallback (if I couldn't clear the garbage out of the config) was to try using firmware 2.0.2 (in the regular firmware update kits, since it is a necessary step to upgrade from anything older than that to 3.x) and see if 10man worked with that firmware.