Curious data and times


I’ve been using kopia compiled (perhaps foolishly) from your git repo. I’m currently using Slackware Linux, Kernel 5.17.1, and go 1.18.0. In a 1TB backup of a linux ext4 partition.

My current kopia build is:

20220405.0.0-45481605 build: 4548160508f5b490eac484888e0146cfd61617a7 from:

I notice that some files and directories are dated:

Access: 2038-01-19 03:14:07.000000000 +0000
Modify: 2038-01-19 03:14:07.000000000 +0000
Change: 2038-01-19 03:14:07.000000000 +0000

I wonder if this is a known problem (end of Unix 32 bit epoch). If not, I’d be happy to try to find the issue.

I’ve been using kopia on this partition since:

20220115.0.0-003b150a build: 003b150a0e75793537aae91289ecf6875aa27809 from:

The directory in question as a real time and date of:

Access: 2022-04-05 03:56:09.827633369 +0100
Modify: 2015-11-24 14:25:54.971913789 +0000
Change: 2020-11-30 23:32:21.783777451 +0000
 Birth: 2020-11-30 22:41:54.539884150 +0000

There are other instances of this time and date anomaly in the kopia mounted file system.

Is this a relic of an old kopia.

I’ve made no further tests, and have not tried to reproduce on a fresh file system as yet.

Thank you for creating kopia and making it available as open source. It’s a very impressive piece of code!

All the best,


Hi Rich,

Me too, using self compiled version from github (due to I need to support one isolated FreeBSD 32bit) and I can’t see such anomaly even on 32bits. What exact files (p, q, s ,x, z or it logs) having such strange timestamps ?


Could you do:

touch 12345
find . -type f -newer 12345

to spot those aliens from a future ?


Thanks for your reply. I’ve had another, closer, look at the data, and it seems that:

a) The source files on disk have incorrect dates. As far as I can see, kopia has not altered the time and dates of any file. These date stamps are not a result of issues with kopia (some data is old, and has been rsync’d multiple times).

b) Kopia changes the time and date of the parent directory to the latest time of any file or directory it contains, right up the hierarchy (not the unix norm). This means that the time and date on directories in kopia backups does not always match the time and date on extant source directories.

I’m sorry if my investigations aren’t too rigorous, I’m a little pushed for time.

All the best,