Sync stopped across all my PCs after updating to FF 20.0 on a Linux PC (mix of FF versions). Logs indicate err 503, so coincidence; will this resolve itself?

Question

I use Sync across a desktop PC and a laptop PC. The desktop runs Vista; the laptop dual-boots Linux and WinXP. Back in the day, I initiated Sync with the desktop, then paired both Firefox installations from each of the laptop's OSes. I sync all available objects. I haven't used Firefox on the laptop/WinXP since before the issue started, and I cannot recall what version I'm at there. I have not attempted to run Firefox from the laptop/WinXP side since the issue started.
My experience has been unremarkable (good) until just a couple of days ago. On the desktop I was already at Firefox ver. 20, while on the laptop's Linux OS, I had been at FF 19.
On the laptop/Linux, I had these recent experiences just before the trouble started:
1) Operating under FF 19, Sync appeared normal. Autoupdate to ver. 20 offered but would never connect and start when selected. Abort and re-check Help->About presented a manual download link for ver. 20 instead.
2) Updated via manual download/install of ver. 20 via suggested link. No issues noticed; Sync appeared normal.
3) Unrelated activities caused me to boot Linux under a root filesystem (including /home) version from the day before I installed ver. 20, and I needed and did run FF ver. 19 again while on this filesystem. Sync _may_ have run and if so, I do not know if it was okay with going "back in time" this way. I was not paying close attention to it at the time, except to say I didn't notice anything unusual about my browsing experience.
4) With the unrelated activities handled, I resumed booting from my normal and current root filesystem, containing FF ver. 20 and my /home and profile from after the upgrade. Again, I did not notice anything obviously wrong.
Later, on the desktop system, the next sync caused all the graphics in my selected personas skin to vanish, leaving just the underlying color style. No other stored personas worked. All sync'ed items appeared to be untouched, but the problem with the personas skins alerted me to somthing being wrong. Attempts to re-sync failed.
Still later, back on the laptop/Linux, the next sync produced the same effect with the personas skins. They remain listed by name, but their source graphics (including addons list icons and text descriptions) have vanished. No other issues are apparent, and no addons or settings, etc. appear to be missing.
Re-sync attempts from either system now fail, but after retrying, indicate the problem is with the server being unavailable due to maintenance...suggesting the Sync service is having an issue, and when it comes back, this will resolve itself. Is that the case, making this just a big coincidence, or is there more going on?
I can provide the saved log files from either the desktop FF ver. 20, or the laptop/Linux FF ver. 20. I cannot provide any logs from the backup root filesystem that contained laptop/Linux FF ver. 19, as that snapshot is now gone. Also, I've not run FF (ver. ?) from the laptop/WinXP side so far during this evolution...but I could provide data and logs from there if it would help.
An excerpt from the most recent sync attempt from my desktop system appears below to illustrate the error:
1366952880580 Sync.Service DEBUG Fetching global metadata record
1366952891895 Sync.Resource DEBUG mesg: GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/meta/global
1366952891895 Sync.Resource DEBUG GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/meta/global
1366952891895 Sync.Service DEBUG Weave Version: 1.22.0 Local Storage: 5 Remote Storage: 5
1366952891896 Sync.Service INFO Sync key is up-to-date: no need to upgrade.
1366952891896 Sync.Service DEBUG Fetching and verifying -- or generating -- symmetric keys.
1366952891897 Sync.SyncKeyBundle INFO SyncKeyBundle being created.
1366952903521 Sync.Resource DEBUG mesg: GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/info/collections
1366952903522 Sync.Resource DEBUG GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/info/collections
1366952903522 Sync.Service INFO Testing info/collections: {"passwords":1365577320.11,"addons":1366750745.5,"tabs":1366950617.59,"clients":1366948047.1,"crypto":1365145328.28,"forms":1366860655.89,"meta":1365145380.12,"bookmarks":1366799244.25,"prefs":1366692754.54,"history":1366950593.58}
1366952903522 Sync.CollectionKeyManager INFO Testing for updateNeeded. Last modified: 0
1366952903522 Sync.Service INFO collection keys reports that a key update is needed.
1366952909816 Sync.SyncScheduler DEBUG Next sync in 3600000 ms.
1366952910712 Sync.Resource DEBUG mesg: GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/crypto/keys
1366952910712 Sync.Resource DEBUG GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/crypto/keys
1366952910713 Sync.CollectionKeyManager INFO Updating collection keys...
1366952910716 Sync.CollectionKeyManager INFO Setting collection keys contents. Our last modified: 0, input modified: 1365145328.28.
1366952910716 Sync.BulkKeyBundle INFO BulkKeyBundle being created for [default]
1366952910716 Sync.CollectionKeyManager INFO Processing downloaded per-collection keys.
1366952910717 Sync.CollectionKeyManager INFO Clearing collection keys...
1366952910717 Sync.CollectionKeyManager INFO Saving downloaded keys.
1366952910717 Sync.CollectionKeyManager INFO Bumping last modified to 1365145328.28
1366952910717 Sync.CollectionKeyManager INFO Collection keys updated.
1366952910717 Sync.Status DEBUG Status.login: success.login => success.login
1366952910717 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366952910731 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366952910732 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366952910733 Sync.SyncScheduler DEBUG Clearing sync triggers and the global score.
1366952910734 Sync.Status INFO Resetting Status.
1366952910735 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366952911057 Sync.SyncScheduler DEBUG Next sync in 3600000 ms.
1366952922945 Sync.Resource DEBUG mesg: GET fail 503 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/info/collections?v=1.22.0
1366952922945 Sync.Resource DEBUG GET fail 503 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/info/collections?v=1.22.0
1366952922946 Sync.ErrorHandler DEBUG Got Retry-After: 300
1366952922946 Sync.Status DEBUG Status.sync: success.sync => error.sync.reason.serverMaintenance
1366952922946 Sync.Status DEBUG Status.service: success.status_ok => error.sync.failed

Answer 1

UPDATE 04260817z -- Suggestions?
The latest Sync log for my desktop system indicates sync completed this time, but there appear to be problems with the personas skins addons. From what I can gather trying my best to interpret the log, something might have happened with one of my paired instances of FF when it transmitted or updated the list of these addons. This log indicates it cannot sync the personas skins because they're not available from the sync store (and they've been partially wiped out from my FF instances). So I guess my desktop's FF knows it has had a given personas skin installed, and when trying to reactivate it, discovers the data is missing, and tries to fetch it from Sync, but sync doesn't have it...stuck.
Have a look at this log, confim my interpretation, and please offer suggestions for how to try to proceed without breaking anything else. Thanks!!
<pre><nowiki>1366961420118 Sync.ErrorHandler DEBUG Flushing file log.
1366961420120 Sync.Status DEBUG Status.service: error.sync.failed_partial => success.status_ok
1366961420121 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366961420121 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366961420166 Sync.ErrorHandler DEBUG Log cleanup threshold time: 1366097420166
1366961420229 Sync.ErrorHandler DEBUG No logs to clean up.
1366961808086 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366963496275 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366963508078 Sync.AddonsReconciler DEBUG Add-on change: onDisabling to [email protected]
1366963508078 Sync.AddonsReconciler DEBUG Ignoring onDisabling for restartless add-on.
1366963508084 Sync.AddonsReconciler DEBUG Add-on change: onDisabled to [email protected]
1366963508085 Sync.AddonsReconciler DEBUG Rectifying state for addon: [email protected]
1366963508085 Sync.AddonsReconciler DEBUG Adding change because enabled state changed: [email protected]
1366963508085 Sync.AddonsReconciler INFO Change recorded for [email protected]
1366963508085 Sync.Tracker.Addons DEBUG changeListener invoked: 4 [email protected]
1366963508085 Sync.Store.Addons DEBUG [email protected] not syncable: add-on not found in add-on repository.
1366963508085 Sync.Tracker.Addons DEBUG Ignoring change because add-on isn't syncable: [email protected]
1366963508088 Sync.AddonsReconciler INFO Saving reconciler state to file: addonsreconciler
1366963508214 Sync.SyncScheduler DEBUG Global Score threshold hit, triggering sync.
1366963508259 Sync.AddonsReconciler DEBUG Add-on change: onEnabling to [email protected]
1366963508259 Sync.AddonsReconciler DEBUG Ignoring onEnabling for restartless add-on.
1366963508294 Sync.AddonsReconciler DEBUG Add-on change: onEnabled to [email protected]
1366963508295 Sync.AddonsReconciler DEBUG Rectifying state for addon: [email protected]
1366963508295 Sync.AddonsReconciler DEBUG Adding change because enabled state changed: [email protected]
1366963508295 Sync.AddonsReconciler INFO Change recorded for [email protected]
1366963508295 Sync.Tracker.Addons DEBUG changeListener invoked: 3 [email protected]
1366963508295 Sync.Store.Addons DEBUG [email protected] not syncable: add-on not found in add-on repository.
1366963508295 Sync.Tracker.Addons DEBUG Ignoring change because add-on isn't syncable: [email protected]
1366963508313 Sync.AddonsReconciler INFO Saving reconciler state to file: addonsreconciler
1366963508317 Sync.Service DEBUG User-Agent: Firefox/20.0.1 FxSync/1.22.0.20130409194949.
1366963508317 Sync.Service INFO Starting sync at 2013-04-26 08:05:08
1366963508317 Sync.SyncScheduler DEBUG Clearing sync triggers and the global score.
1366963508318 Sync.Status INFO Resetting Status.
1366963508318 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok
1366963508466 Sync.SyncScheduler DEBUG Global Score threshold hit, triggering sync.
1366963508489 Sync.Service DEBUG User-Agent: Firefox/20.0.1 FxSync/1.22.0.20130409194949.
1366963508489 Sync.Service INFO Starting sync at 2013-04-26 08:05:08
1366963508489 Sync.Service DEBUG Exception: Could not acquire lock. Label: "service.js: sync". No traceback available
1366963508489 Sync.Service INFO Cannot start sync: already syncing?
1366963509587 Sync.Resource DEBUG mesg: GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/info/collections
1366963509587 Sync.Resource DEBUG GET success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/info/collections
1366963509588 Sync.Service DEBUG Fetching global metadata record
1366963509588 Sync.Service DEBUG Weave Version: 1.22.0 Local Storage: 5 Remote Storage: 5
1366963509588 Sync.Service INFO Sync key is up-to-date: no need to upgrade.
1366963509588 Sync.Service DEBUG Fetching and verifying -- or generating -- symmetric keys.
1366963509588 Sync.Service INFO Testing info/collections: {"passwords":1365577320.11,"tabs":1366960299.53,"clients":1366954606.81,"crypto":1365145328.28,"forms":1366860655.89,"meta":1365145380.12,"prefs":1366957189.91,"bookmarks":1366956848.81,"addons":1366750745.5,"history":1366961119.98}
1366963509588 Sync.CollectionKeyManager INFO Testing for updateNeeded. Last modified: 1365145328.28
1366963509588 Sync.Synchronizer DEBUG Refreshing client list.
1366963509589 Sync.Engine.Clients INFO 0 outgoing items pre-reconciliation
1366963509590 Sync.Engine.Clients INFO Records: 0 applied, 0 successfully, 0 failed to apply, 0 newly failed to apply, 0 reconciled.
1366963509591 Sync.Synchronizer INFO Updating enabled engines: 3 clients.
1366963509593 Sync.Engine.Bookmarks INFO 0 outgoing items pre-reconciliation
1366963509594 Sync.Engine.Bookmarks INFO Records: 0 applied, 0 successfully, 0 failed to apply, 0 newly failed to apply, 0 reconciled.
1366963509597 Sync.Engine.Forms INFO 2 outgoing items pre-reconciliation
1366963509598 Sync.Engine.Forms INFO Records: 0 applied, 0 successfully, 0 failed to apply, 0 newly failed to apply, 0 reconciled.
1366963509611 Sync.Engine.Forms INFO Uploading all of 2 records
1366963509612 Sync.Collection DEBUG POST Length: 785
1366963510491 Sync.Collection DEBUG mesg: POST success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/forms
1366963510491 Sync.Collection DEBUG POST success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/forms
1366963510493 Sync.Engine.History INFO 13 outgoing items pre-reconciliation
1366963510494 Sync.Engine.History INFO Records: 0 applied, 0 successfully, 0 failed to apply, 0 newly failed to apply, 0 reconciled.
1366963510521 Sync.Engine.History INFO Uploading all of 13 records
1366963510522 Sync.Collection DEBUG POST Length: 6875
1366963510921 Sync.Collection DEBUG mesg: POST success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/history
1366963510921 Sync.Collection DEBUG POST success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/history
1366963510923 Sync.Engine.Passwords INFO 0 outgoing items pre-reconciliation
1366963510924 Sync.Engine.Passwords INFO Records: 0 applied, 0 successfully, 0 failed to apply, 0 newly failed to apply, 0 reconciled.
1366963510925 Sync.Engine.Prefs INFO 1 outgoing items pre-reconciliation
1366963510926 Sync.Engine.Prefs INFO Records: 0 applied, 0 successfully, 0 failed to apply, 0 newly failed to apply, 0 reconciled.
1366963510991 Sync.Engine.Prefs INFO Uploading all of 1 records
1366963510992 Sync.Collection DEBUG POST Length: 21951
1366963511249 Sync.Collection DEBUG mesg: POST success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/prefs
1366963511249 Sync.Collection DEBUG POST success 200 https://phx-sync299.services.mozilla.com/1.1/rj4aro36czb4apyh6zydowitfljhqed2/storage/prefs
1366963511250 Sync.Engine.Tabs DEBUG First sync, uploading all items
1366963511251 Sync.Engine.Tabs INFO 1 outgoing items pre-reconciliation
1366963518535 Sync.AddonsReconciler DEBUG Add-on change: onEnabling to {972ce4c6-7e08-4474-a285-3208198ce6fd}
1366963518535 Sync.AddonsReconciler DEBUG Ignoring onEnabling for restartless add-on.
1366963518568 Sync.AddonsReconciler DEBUG Add-on change: onEnabled to {972ce4c6-7e08-4474-a285-3208198ce6fd}
1366963518568 Sync.AddonsReconciler DEBUG Rectifying state for addon: {972ce4c6-7e08-4474-a285-3208198ce6fd}
1366963518568 Sync.AddonsReconciler DEBUG Adding change because enabled state changed: {972ce4c6-7e08-4474-a285-3208198ce6fd}
1366963518568 Sync.AddonsReconciler INFO Change recorded for {972ce4c6-7e08-4474-a285-3208198ce6fd}</nowiki></pre>
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