Re: backup manifests

Hi,

In a negative test scenario, if I changed size to -1 in backup_manifest, pg_validatebackup giving

error with a random size number.

[edb@localhost bin]$ ./pg_basebackup -p 5551 -D /tmp/bold --manifest-checksum 'SHA256'

[edb@localhost bin]$ ./pg_validatebackup /tmp/bold
pg_validatebackup: backup successfully verified

--change a file size to -1 and generate new checksum.

[edb@localhost bin]$ vi /tmp/bold/backup_manifest
[edb@localhost bin]$ shasum -a256 /tmp/bold/backup_manifest
c3d7838cbbf991c6108f9c1ab78f673c20d8073114500f14da6ed07ede2dc44a  /tmp/bold/backup_manifest
[edb@localhost bin]$ vi /tmp/bold/backup_manifest

[edb@localhost bin]$ ./pg_validatebackup /tmp/bold
pg_validatebackup: error: "global/4183" has size 0 on disk but size 18446744073709551615 in the manifest

Thanks & Regards,

Rajkumar Raghuwanshi

On Thu, Mar 5, 2020 at 9:37 AM Suraj Kharage <suraj.kharage@enterprisedb.com> wrote:

On Wed, Mar 4, 2020 at 7:21 PM tushar <tushar.ahuja@enterprisedb.com> wrote:

Hi,

There is a scenario in which i add something inside the pg_tablespace directory , i am getting an error like-

pg_validatebackup: * manifest_checksum = 77ddacb4e7e02e2b880792a19a3adf09266dd88553dd15cfd0c22caee7d9cc04
pg_validatebackup: error: "pg_tblspc/16385/PG_13_202002271/test" is present on disk but not in the manifest

but if i remove 'PG_13_202002271 ' directory then there is no error

[centos@tushar-ldap-docker bin]$ ./pg_validatebackup data
pg_validatebackup: * manifest_checksum = 77ddacb4e7e02e2b880792a19a3adf09266dd88553dd15cfd0c22caee7d9cc04
pg_validatebackup: backup successfully verified

This seems expected considering current design as we don't log the directory entries in backup_manifest. In your case, you have tablespace with no objects (empty tablespace) then backup_manifest does not have any entry for this hence when you remove this tablespace directory, validator could not detect it.

We can either document it or add the entry for directories in the manifest. Robert may have a better idea on this.

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Thanks & Regards, 

Suraj kharage, 

EnterpriseDB Corporation, 

The Postgres Database Company.

-- 
regards,tushar
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