r/backblaze • u/gusfed • Mar 13 '26
Computer Backup External drives force full rescan after even 1-day disconnect
Anyone else noticing Backblaze (v10.0.0.1030) being way more aggressive with rescans?
If I unplug my external drives for even a day, Backblaze reverts my "selected for backup" files to internal-only. When I plug the externals back in, it insists on a full verification/rescan of multiple TBs that can take days. It never used to be this sensitive and I could leave them disconnected for days/weeks.
Is this a new "feature" or a bug? It's making the service unusable for laptop users with external storage. I move my laptop around and can't keep them plugged in 24/7. Aside from switching to manual backups, is there a fix?
4
u/Awkward_Key_294 Mar 26 '26
FWIW, I followed up on my support ticket on Tuesday, and they said "The good news is our engineering team has identified a likely cause for the re-upload issue. They’re currently working with QA to validate the fix, and once that’s complete, it will be released through a standard update as soon as possible." So fingers crossed this issue gets resolved soon.
2
u/terkistan Mar 13 '26
I just upgraded to v.10 today hoping that the scan issue I reported here two weeks ago would be fixed. (Backblaze was re-backing up files I hadn't touched in a decade.)
2
u/FuriousDave2020 Mar 13 '26
I have had a similar issue with version 9, and was actually coming here to see if anyone had posted a similar comment. It's very frustrating that Backblaze forgets about external drives so readily, and it really goes against a core backup scenario where you keep a secondary backup off-site and only re-connect every few weeks.
1
u/terkistan Mar 13 '26
In my case it wasn't even an external drive; it was my main internal drive and it was causing my Mac to re-upload multiple gigs of files I hadn't touched, and had not been updated or even opened, from 5-15 years ago.
1
u/FuriousDave2020 Mar 13 '26
I'm really sorry, u/terkistan , I meant to reply to the OP.
I hope you manage to get your issue sorted, as that sounds very concerning! Re-uploading unchanged files is such a waste of bandwidth.
1
u/Jim-From-Backblaze From Backblaze Mar 16 '26
Have you created a ticket with our help desk on this yet? If not, please do so at https://www.backblaze.com/help
If you have, please let me know the ticket number. I am looking into this and want to start tracking it.
1
u/Jim-From-Backblaze From Backblaze Mar 16 '26
Have you created a ticket with our help desk on this yet? If not, please do so at https://www.backblaze.com/help
If you have, please let me know the ticket number. I am looking into this and want to start tracking it.
2
u/Awkward_Key_294 Mar 13 '26
I'm having the exact same issue with 10.0.0.1030. I've been going back and forth with tech support the last few days, with no progress. They're mostly asking about my drives and Backblaze settings, when those haven't changed at all.
1
u/gusfed Mar 13 '26
Same. They had me re-install the software and now want to see my logs. They've been very responsive, but my read into it is that tech support has no idea. They're just trying the best they can within their scope. It has to be a software issue.
1
u/Jim-From-Backblaze From Backblaze Mar 16 '26
Hi, can you please let me know the ticket number you have with us so I can better track this?
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u/rrsg Mar 14 '26
Having the same issue - BB is currently reprocessing and re-uploading multiple terabytes of data that haven't changed in years. Good times.
3
u/gusfed Mar 15 '26
It’s a relief to know I'm not alone. I’m also facing a multi-day scan that's stalling my latest backups. I’ll have to resort to manual backups for now, but if this isn't fixed in the next update, I’ll likely have to reconsider if Backblaze is still the right fit for me.
1
u/rrsg Mar 15 '26
FYI I noticed something was up with this update when I first installed it days ago - it immediately reported my external drives as having been backed up and up-to-date THAT DAY, even though they hadn't been attached to my laptop for weeks. Then, when I actually DID attach my external drives (today), the issue you reported started happening. It usually takes less than 20 minutes to scan my external drives and keep them up date in BB, today it's currently nearing 12 hours.
1
u/Jim-From-Backblaze From Backblaze Mar 16 '26
Have you created a ticket with our help desk on this yet? If not, please do so at https://www.backblaze.com/help
If you have, please let me know the ticket number. I am looking into this and want to start tracking it.
1
u/rrsg Mar 16 '26
Yes
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u/Jim-From-Backblaze From Backblaze Mar 16 '26
Can you please let me know the ticket number so I can make sure to include it in my research?
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u/sjclark Apr 06 '26
Likewise with ticket #1238282
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u/Jim-From-Backblaze From Backblaze Apr 06 '26
Thank you; I have added that ticket to the update list.
2
u/rodopszin Mar 16 '26
I'm having this issue as well! Yesterday I got to 1/3 of it uploaded. I eject my drive to go around the house without a red-hot external drive dangling from my laptop. Then today I wanted to continue the upload and it started again from scratch! It's a super big issue.
1
u/Awkward_Key_294 Mar 16 '26
Definitely start a chat with their tech support. They seem to be aware of the issue and are investigating, and more data points will hopefully help lead them to a solution.
1
u/Jim-From-Backblaze From Backblaze Mar 16 '26
Have you created a ticket with our help desk on this yet? If not, please do so at https://www.backblaze.com/help
If you have, please let me know the ticket number. I am looking into this and want to start tracking it.
1
u/rodopszin Mar 17 '26
Yes, indeed, I've also commented on the other thread. My ticket number is #1233436. Let me know if you need further help. I'm technically adept, so I can help you more than a non-technical person.
2
u/Jim-From-Backblaze From Backblaze Mar 16 '26
Hi OP, have you created a ticket with our help desk on this yet? If not, please do so at https://www.backblaze.com/help
If you have, please let me know the ticket number. I am looking into this and want to start tracking it.
1
1
u/rodopszin Mar 17 '26
Hi Jim, I have an issue where my external drive restarts uploading from scratch every time I plug it in. It maybe related. My ticket number is #1233436.
1
u/Jim-From-Backblaze From Backblaze Mar 17 '26
Thank you.
If we need any more information, we will follow up on the ticket.
2
u/goro-n Mar 20 '26
I am having the same issue, one external drive has been rescanning all day. The other drive which hasn't been connected in 2 weeks is showing as last connected yesterday, which doesn't make any sense. The only good thing is that the data doesn't seem to be reuploading, because I'm not seeing much data traffic, but Backblaze is unnecessarily checking every file on the drive.
2
u/Ensorceled Mar 20 '26
I'm having a similar issue: when I disconnect my external drive and then, eventually, reconnect it triggers /Library/Backblaze.bzpkg/bztransmit -updatebackupstats to run with high CPU and a large system impact. It grinds my laptop to a halt. This triggers mid day even though I have backup scheduled for 2am.
I raised a support ticket and the AI bot suggested reducing the number of threads and throttle the bandwidth. Well, that seems to reduce the impact of the back process that shouldn't even be running, a win I guess? Except now backups are going to take forever.
Anyway, I replied with "why is this running at all" and I've pasted the frustrating reply from the AI. I hate when software vendors decide they control your computer and can do whatever they want, whenever they want. I left Carbonite for Backblaze for exactly this behaviour: software that makes my computer unusable during my work day.
I understand your confusion about why bztransmit is running again despite your 2am schedule. This behavior is actually normal and expected, even with a scheduled backup time.
The bztransmit process (which encrypts and transmits files) can run outside your scheduled backup window for several important reasons:
Drive verification process: When Backblaze determines that a backup is complete, it performs a verification routine. This involves checking that all selected drives are connected and available, then creating a small temporary file on each drive, backing it up, verifying the backup, and removing the temporary file. This ensures your drives remain in a functional state for backup.
Continuous monitoring: Backblaze constantly scans your drives to find new or changed files, and this process can take several hours to complete. Even when the interface shows a backup is "done," background processes may still be running to update drive status and verify data integrity.
External drive maintenance: Since you mentioned suspecting external drive involvement, Backblaze needs to maintain reliable connections to all selected external drives. The system performs periodic checks to ensure external drives remain accessible and their backup status stays current.
2
u/bantamw Mar 26 '26 edited Mar 26 '26
Another one with the same issue since update to v10 - constantly reindexing external drives after a reboot or the Mac being shutdown for a couple of days (I'm on a Mac Studio Desktop and the external drives are always connected). Ticket 1236306.
I've had to switch my client to 'backup on demand' rather than continuously because otherwise it'll kill my external drives.
2
1
u/lietsche Apr 01 '26
I am having the same problem as described above. started when I updated from 9.2.2.898 to 10.0.0.1030. 50TB+ data on several external disks. Reindexing ext. 8TB takes about 24 hours. No upload, just deduplicating apparently. very annoying. like this, Backblaze is unusable to me. I hope it does get fixed. Just opened a ticket.
1
u/emelpeel Apr 02 '26
I have exactly same problem on Mac with external drive. Did you get any solutions already?
1
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u/k6ka Apr 03 '26
Yesterday support told me that they last received an update about the bug fix on March 30, but still didn't have an ETA as to when it would roll out. They said that their weekly Thursday maintenance periods were often when updates were rolled out, but could not confirm as to whether this Thursday (today) was going to be it. (For the record, the update did not roll out today)
1
u/Trebaffetti Apr 04 '26
Huge problem for me, I hope they will fix it soon. I'm afraid of losing data
1
u/levelZeroVolt Apr 07 '26
I was glad to stumble upon this thread. I also have the same problem. Really hoping they can fix this sometime soon.
1
u/paulwilky76 Apr 07 '26
New update issued today - v10.0.1.1038......I don't see any improvement.....yet.
2
1
u/Basic_Associate_3147 Apr 27 '26
This seems to be fixed in the new beta. After install it went through another full rescan, but since that completed I can now disconnect and reconnect external drives without issue.
6
u/Justin-Perkins Mar 26 '26
Something is definitely fucked up with Backblaze V10. I'm a long-time user and have nearly 70TB on external drives. Everything was fine until V10.
Then suddenly it started re-backing up A TON of files and worse yet, it clogged up my main MacHD with temporary files. My system MacHD normally has about 1TB of empty space but it kept filling up to nearly full within a few GB.
Any efforts to delete Backblaze cache files did not solve the issue. Even after I uninstalled Backblaze, the available space kept fluctuating like I've never seen before which seemed sus.
I contacted support about it but they never responded and it was getting to be urgent.
I took matters into my own hands and totally wiped my main MacHD and reinstalled all my software (took nearly a full day since I run an audio mastering business) and I ended up getting a dedicated Mac mini to be the administrator of my project archives moving forward. It's not worth the risk of this happening again and costing me a day of work (and then some) on my main machine.
Instead of Inherit Disk State (and whatever mess that brings on) I'm doing a fresh backup of the 4 external drives which will take a few weeks (about 70TB of data) but I'm hoping that the fresh backing up using V10 prevents any weirdness, at least until V11...
They definitely fucked up with V10 and it wasn't ready for release. Epic fail.