Re: BUG #17156: pg_restore: [custom archiver] WARNING: ftell mismatch with expected position -- ftell used

At Tue, 24 Aug 2021 14:25:50 +0900, Masahiko Sawada <sawada.mshk@gmail.com> wrote in 
> On Mon, Aug 23, 2021 at 7:31 PM PG Bug reporting form
> <noreply@postgresql.org> wrote:
> >
> > The following bug has been logged on the website:
> >
> > Bug reference:      17156
> > Logged by:          Ashutosh Kumar
> > Email address:      ashutosh.kumar@morningstar.com
> > PostgreSQL version: 10.18
> > Operating system:   RHEL
> > Description:
> >
> > Getting below warning when I am restoring the backup file :
> >
> > Warning Message : pg_restore: [custom archiver] WARNING: ftell mismatch with
> > expected position -- ftell used
> >
> > Backup was taken with below command :
> >
> > pg_dump -h'127.0.0.1'  -p 5432 -U (username)  -Fc  databasename >
> > backupfile.sql
> >
> > I am restoring it with pg_restore when i got the above warning.
> 
> Could you share the exact pg_restore command with the arguments you executed?
> 
> What's is the size of the backup? Are both Postgres servers that you
> took/restored the backup from/to are RHEL?
> 
> Could you try to execute pg_dump without a pipe and restore it and see
> the same error happens? That is, please execute "pg_dump -h'127.0.0.1'
>  -p 5432 -U (username)  -Fc  databasename -f backupfile.sql".

That error means when reading a seekable source, the file pointer
ftello returns doesn't consistent with how many bytes pg_restore has
read, or ftello returned an error.  Considering that the path is very
ancient, the latter likely to happen.  If the failure is reproducible,
running pg_restore with strace could show something helpful.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center