Re: Can't write '/var/svn/NetBeansProjects/db/txn-current' atomically

hi.  lurker of the thread.

but was curious, when u find the odd/weird issue, do any of the free
LLM/models, or google's ask gemini/browser AI ever help?

thanks


On Wed, Aug 5, 2026, 4:13 PM Daniel Sahlberg <[email protected]>
wrote:

> Hi,
>
> I still believe there is a kernel security module doing funny business,
> even though I stand corrected that it should be AppArmor and not SELinux. I
> have not really worked with either but I guess they are more or less the
> same.
>
> My Ubuntu 26.04 (running on WSL) has some rules in /etc/apparmor.d that
> seems to affect Apache httpd but I don't understand it well enough to say
> if this is the reason.
>
> The documentation suggest you should be able to search the system log for
> any denied requests - I would start there and see if it leads to something:
> https://www.apparmor.net/#what-does-it-look-like-in-practice
>
> Hope it helps!
>
> Cheers,
> Daniel
>
>
> Den ons 5 aug. 2026 kl 20:44 skrev falco philmarks.net <
> [email protected]>:
>
>> Jeff, Daniel,
>>
>> Thanks for weighing in here.  To provide some more information:
>>
>> - I tried the chown/chmod commands suggested by Jeff, including some
>> interim reboots of both the client and the server, but the problem
>> persisted.  Here is what appeared with the NetBeans development environment
>> running on the Windows client - NetBeans is using some convoluted
>> arguments, but I can reproduce the problem doing simple command-line
>> commits from a suitable project tree built outside of NetBeans:
>>
>> (some newlines inserted for clarity)
>> ==[IDE]== Aug 5, 2026, 1:37:07 PM Preparing Commit...
>> ==[IDE]== Aug 5, 2026, 1:37:09 PM Preparing Commit... finished.
>> ==[IDE]== Aug 5, 2026, 1:37:13 PM Committing...
>> commit --force-log -F
>> C:\Users\phil\AppData\Local\Temp\vcs-1785951411537\vcs-1785951433994\svn_16404019375185975522
>>     --targets
>> C:\Users\phil\AppData\Local\Temp\vcs-1785951411537\vcs-1785951433994\svn_372745134647644105
>>     --config-dir
>> C:\Users\phil\AppData\Roaming\NetBeans\29\config\svn\config
>> --non-interactive --username philmarks
>>     --password ******
>> svn: E000001: Commit failed (details follow):
>> svn: E000001: Can't write '/var/svn/NetBeansProjects/db/txn-current'
>> atomically
>>
>> ==[IDE]== Aug 5, 2026, 1:37:20 PM Committing... finished.
>>
>>
>> - I had previously run some similar chown/chmod commands suggested in the
>> Ubuntu subversion community Wiki, on both the LTS 24.04 and 26.04 servers -
>> they ran without error in both, but only produced the desired results in
>> the former:
>>
>>    $ cd /home/svn
>>    $ sudo chown -R www-data:subversion myproject
>>    $ sudo chmod -R g+rws myproject
>>
>>
>> - To Daniel's point, I had tried the other day to look into the AppArmor
>> environment, but it was a bit beyond my ancient Linux/Unix knowledge.  I
>> ran a bunch of commands to provide you with a bit more information,
>> including the -Z option to ls (sorry if the results look a bit choppy). The
>> question marks after the group name appear to be the sole new information
>> produced by -Z:
>>
>> $ ls -alZ /var/svn/NetBeansProjects
>> total 32
>> drwxrwsr-x 6 www-data subversion ? 4096 Aug  4 11:38 .
>> drwxr-xr-x 3 root     root       ? 4096 Aug  4 11:37 ..
>> -rw-rwSr-- 1 www-data subversion ?  246 Aug  4 11:38 README.txt
>> drwxrwsr-x 2 www-data subversion ? 4096 Aug  4 11:38 conf
>> drwxrwsr-x 6 www-data subversion ? 4096 Aug  5 13:37 db
>> -rw-rwSr-- 1 www-data subversion ?    2 Aug  4 11:38 format
>> drwxrwsr-x 2 www-data subversion ? 4096 Aug  4 11:38 hooks
>> drwxrwsr-x 2 www-data subversion ? 4096 Aug  4 11:38 locks
>> total 68
>>
>> $ ls -alZ /var/svn/NetBeansProjects/db
>> drwxrwsr-x 6 www-data subversion ?  4096 Aug  5 13:37 .
>> drwxrwsr-x 6 www-data subversion ?  4096 Aug  4 11:38 ..
>> -rw-rwSr-- 1 www-data subversion ?     2 Aug  4 14:30 current
>> -rw-rwSr-- 1 www-data subversion ?    41 Aug  4 11:38 format
>> -rw-rwSr-- 1 www-data subversion ?     5 Aug  4 11:38 fs-type
>> -rw-rwSr-- 1 www-data subversion ? 10835 Aug  4 11:38 fsfs.conf
>> -rw-rwSr-- 1 www-data subversion ?     2 Aug  4 11:38 min-unpacked-rev
>> -rw-rwSr-- 1 www-data subversion ?  8192 Aug  4 14:30 rep-cache.db
>> -rw-rw-r-- 1 www-data subversion ?     0 Aug  4 14:30 rep-cache.db-journal
>> drwxrwsr-x 3 www-data subversion ?  4096 Aug  4 11:38 revprops
>> drwxrwsr-x 3 www-data subversion ?  4096 Aug  4 11:38 revs
>> drwxrwsr-x 2 www-data subversion ?  4096 Aug  4 14:30 transactions
>> -rw-rwSr-- 1 www-data subversion ?     2 Aug  4 14:30 txn-current
>> -rw-rwSr-- 1 www-data subversion ?     0 Aug  4 11:38 txn-current-lock
>> drwxrwsr-x 2 www-data subversion ?  4096 Aug  4 14:30 txn-protorevs
>> -rw-rwSr-- 1 www-data subversion ?    74 Aug  4 11:38 uuid
>> -rw-rwSr-- 1 www-data subversion ?     0 Aug  4 11:38 write-lock
>>
>> $ getent group subversion
>> subversion:x:1002:www-data,phil
>>
>> $ getent group www-data
>> www-data:x:33:phil
>>
>> $ cat /etc/apache2/dav_svn.passwd
>> philmarks:$apr1$qQTMuFXy$UUecFm.JGgP9FDxE7GHU6/
>>
>> $ cat /etc/subversion/passwd
>> philmarks:$apr1$AHboqPhe$Gm5w8a2BSJBxKUxHHGFC6.
>> phil:$apr1$alKGx5Mq$w2mlJm2c.Z10oz8lkseMh/
>> philip:$apr1$tSpsAsJ5$cMmszgMwIzWv1S7vSeemZ1
>>
>>
>> - Note that the username passed from the client environment with the
>> commits is philmarks, rather than phil (which is the admin user on the
>> server). I was under the impression that the usernames passed to Apache and
>> the local subversion usernames were in different spaces
>> (/etc/apache2/dav_svn.passwd and /etc/subversion/passwd respectively). In
>> any event, user philmarks is present in both files with the same password,
>> so I don't think that can be the problem - the test server, where things
>> work as expected, is set up the same way.
>>
>>
>> Please let me know if there's any information I can provide that might
>> help.
>>
>> Phil
>>
>>
>>
>> -----Original Message-----
>> From: Jeffrey Walton <[email protected]>
>> Sent: Wednesday, August 5, 2026 12:28 PM
>> To: [email protected]
>> Cc: [email protected]
>> Subject: Re: Can't write '/var/svn/NetBeansProjects/db/txn-current'
>> atomically
>>
>> On Wed, Aug 5, 2026 at 12:23 PM Daniel Sahlberg <
>> [email protected]> wrote:
>> >
>> > ons 5 aug. 2026 kl. 17:49 skrev Jeffrey Walton <[email protected]>:
>> >>
>> >> On Wed, Aug 5, 2026 at 11:30 AM falco philmarks.net <
>> [email protected]> wrote:
>> >> >
>> >> > Is anyone else experiencing problems with repository changes (e.g.,
>> commits) submitted over https to server running Apache2 on Ubuntu LTS 26.04?
>> >> >
>> >> > When trying to commit changes remotely, or add new projects to a
>> repository, the following error messages are returned:
>> >> >
>> >> > E000001: Commit failed (details follow):
>> >> > E000001: Can't write '/var/svn/NetBeansProjects/db/txn-current'
>> >> > atomically
>> >> >
>> >> > And I find the following lines in the Apache error log:
>> >> >
>> >> > [Tue Aug 04 14:43:00.903971 2026] [:error] [pid 9352:tid 9369]
>> >> > [client 10.1.0.26:57765] Can't write
>> >> > '/var/svn/NetBeansProjects/db/txn-current' atomically  [500, #1]
>> >> > [Tue Aug 04 14:43:00.903980 2026] [:error] [pid 9352:tid 9369]
>> >> > [client 10.1.0.26:57765] Can't set permissions on
>> >> > '/var/svn/NetBeansProjects/db/svn-2iqlzz'  [500, #1] [Tue Aug 04
>> >> > 14:43:00.903988 2026] [:error] [pid 9352:tid 9369] [client
>> >> > 10.1.0.26:57765] Can't set permissions on
>> >> > '/var/svn/NetBeansProjects/db/svn-2iqlzz': Operation not permitted
>> >> > [500, #1]
>> >> >
>> >> > At first glance this looks like a simple permissions problem, and I
>> have reviewed numerous internet postings showing similar (though not
>> identical) error messages.  But I have looked very closely at the settings
>> for all the relevant files and made sure that they are owned by www-data
>> and within a group named “subversion” group that includes both www-data and
>> my own personal ID on the server.
>> >> >
>> >> > I have no problem adding projects or making commits locally on the
>> server in question (repository access via file:/// …..). I have no problems
>> viewing the repository from a Windows 11 machine using the Tortoise SVN
>> repository browser. I have no problems checking out a project into NetBeans
>> on the same Windows client, or onto a different client machine that runs
>> Ubuntu LTS 24.04.
>> >> >
>> >> >
>> >> > Before setting up the environment on the 26.04 machine that reports
>> the errors, I tried a dry run on a parallel testing environment on another
>> server machine that also happens to run Ubuntu LTS 24.04 (i.e., this is a
>> different machine from the 24.04 client mentioned in the previous
>> paragraph). That test environment experiences no problems with remote
>> changes – in particular, commits sent via https from NetBeans instances
>> running on client machines function as expected.  There are of course
>> version level differences in the Apache and subversion software on these
>> two servers, but when I compare the Apache and dav_svn config files between
>> them I see no significant differences; likewise the permissions settings on
>> the files in the two repositories.
>> >> >
>> >> > At this stage the repository concerned is not in production mode and
>> does not contain anything that I cannot afford to lose.  So I have also
>> tried deleting and recreating it from scratch, as well as uninstalling and
>> reinstalling Apache and subversion and related packages on the 26.04 LTS
>> machine intended as the long-term host.
>> >> >
>> >> > Does anyone have any suggestions as to what I should try next?
>> >> >
>> >> > Any help would be appreciated.
>> >>
>> >> I think you need to issue the following commands:
>> >>
>> >>     sudo chown -R www-data:subversion /var/svn/NetBeansProjects
>> >>     sudo chmod -R ug+rwX /var/svn/NetBeansProjects
>> >>
>> >> And then see if the problem is still present.
>> >>
>> >> Also, does your subversion group include the same principals as the
>> >> www-data group?
>> >
>> > Any chance that SELinux is doing its magic?
>>
>> At first, I thought that smelled of SELinux, too.  But he said Ubuntu,
>> and Ubuntu uses AppArmor.
>>
>> Fedora and Red Hat would use SELinux, and `ls -alZ` would be one of my
>> goto tools.
>>
>> Jeff
>>
>