hello again to everyone,
i posted earlier on, but have been following at least 4 threads on this mavericks and hd issue, including pegasus units.
in summary, i have two bloated new imac systems (jan 2013), 3 27" displays, pegasus r4's, 3tb usb wd hds, etc.
both went to mavericks, never having installed any promise software, utilities, drivers, whatever. both worked flawlessly as time machine archives, and weekly time machine backups to the wd drives (also no wd softare or drivers ever installed, immediately reformatted on installation as we do all ext hds).
one system reported time machine unavailable for 5 days but that was ignored (not my system...) and my imac did the same immediately after installing mavericks... where as i freaked, tried a long list of 'fixes' from reformatting, re-installing mavericks (3 times), hard reset of time michine, repairs to ssd in imac and pegasus, all to no avao=il.
i reported the problem to promice on their support site, only to discover just yesterday that you must have pop-ups unblocked or you can never get to see their responses... yah, they gotta fix that, and a few other things.
so, i ranted here and other threads like a madman (like most others have done) and promise contacted me directly and were enormously helpful in sorting most of this out... it DOES seem to be a combo-problem, with just a tad of error, err, not-error-handling added in by mavericks.
wd has already issued lots of 'yatta' and other thread-posts about their complicity, so i'll skipp all that here.
for the pegasus, my system, after loading a new updated promiseutils, and after promise had me update the pegasus firmware, and after promise gave me good instructions on command lines that needed to be done via 'terminal' because their utility doesn't actually do it under mavericks yet... hmmm, they'll fix that eventually too, but they did jump in here to honestly help (go back in the posts and you'll find victor's email address at promise).
and a yton of littl epicky things to do... but finally it all works perfectly again:
so, here's the pointers i learned:
in general: go to system preferences, spotlight, and add your externals drives (especially your time machine drive) to the privacy window so that processor hog pita spotlight doesn't spend days indexing it!). it 'seems' that if spotlight is indexing it time machine will choke faster than a yorkie with a chicken bone!
pegasus: for sure, contact promise via email to victor as online support is lacking, takes along time, and... well, they aren't the brains behind promise support, victor and his guys are. make sure you have the latest promiseutils installed and working, and thus you can get the latest firmware update... afterwards, power-down your pegasus unit, and cold boot your system then repwoer the pegasus. after several cold mavericks reboots, and 2 weeks of time, suddenly mavericks discovers a 'new thunderbolt bridge'??? ***, who snuck a tiny mavericks update in while i was blind? seriously... this imac has been running since january and suddenly it has a new thunderbolt bridge two weeks after installing mavericks? yorkie >> chicken bone.
IF your promiseutils app (you must run it) shows that any of their toshiba (or whatever) hds have a 'bad block' that has supposedly been isolated and the r4/r6 should work anyway as designed to be a good raid system... mavericks >> yorkie >> chicken bone!! i suspect (have no proof and don't want to go look for any either) that mavericks will choke on any timeout of error message/state from any hd, and particularly a fw hd or thunderbolt drive, regardless of what their 'software' tries to do. it appears any timeout and mavericks will take an apocalyptic viewpoints and try to eliminate the alien in your system and re-write its DNA. as soon as i 'hot-yanked' that not-even-failed- hd from the pegasus, poof, it handled the raid issue like it was supposed to, and time machine worked, and mavericks stopped going all terminatrix on it.
the other imac system with the odd time machime failure? meh- 5 or 6 days later it just started working after spotlight (under mavericks) finally finshed hogging it and using 90+ percent of the processors. it still doesn't have a firmware update, and it still doesn't have promiseutils on it... so, betcha it doesn't have a 'bad block' anywhere either. we just keep a little statue of bhudda close by with a little bit of rice and fruit going rotten, have a crucifix on the wall, and tiptoe silently near it (mostly to just not wake up that scientist, i think).
ps. there's no way i am going to put mavericks on my imac at home, yet...