Re: Verify or dump pgdata files

Use PgBackRest or pg_basebackup. Not only do they correctly handle wal
files, but do checksums.

On Mon, Oct 21, 2024 at 11:51 AM Murthy Nunna <mnunna(at)fnal(dot)gov> wrote:

> Hi Muhammad,
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> Thank you for responding to my query.
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> I don’t think checksum method will work in my situation because the source
> file would have changed by the time I run checksum. So, the checksum (or
> diff) will be different.
>
> I am doing rsync of active cluster.
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> What I am looking for is physical (structural) verification of target file
> such as beginning block and end block, beginning of file and end of file
> etc. All I want to know is “completeness” and “readability” of the file by
> postgres.
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> Thanks.
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> *From:* Muhammad Ikram <me(dot)mikram(at)gmail(dot)com>
> *Sent:* Sunday, October 20, 2024 10:34 PM
> *To:* Murthy Nunna <mnunna(at)fnal(dot)gov>
> *Cc:* pgsql-admin(at)postgresql(dot)org
> *Subject:* Re: Verify or dump pgdata files
>
>
>
> [EXTERNAL] – This message is from an external sender
>
> Hi,
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> Could you use diff ? e.g.
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> diff -qr /var/lib/pgsql/15/data /tmp/data
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> Or
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> pg_checksums --verify --data-dir=/pgdata (for checksum enabled databases)
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> or do checksum on source and target and take diff between two checksum
> generated files e.g.
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> cd /pgdata
> find . -type f -exec sha256sum {} \; > /tmp/source_checksums.txt
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> Regards,
>
> Ikram
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> On Sun, Oct 20, 2024 at 4:45 AM Murthy Nunna <mnunna(at)fnal(dot)gov> wrote:
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> Hi,
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> We are currently using pg_waldump to verify integrity of WAL files after
> archiving them in external storage. If the WAL is incomplete pg_waldump
> returns error, which is great.
>
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> Similarly, I am wondering if there is any utility that can be used against
> data files in /pgdata. Just to verify after “rsync” of /pgdata.
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> Thanks in advance for your response.
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