Wal-G unable to restore incremental backup from Stolon

[lexasoft123]

Hello!

When I'm trying to fetch incremental backup, I get following errors. If the latest backup is full, everything is good.

INFO: 2021/03/17 14:55:33.642875 Finished extraction of part_811.tar.br
INFO: 2021/03/17 14:55:33.642937 Finished decompression of part_811.tar.br
INFO: 2021/03/17 14:55:33.678166 Finished extraction of pg_control.tar.br
INFO: 2021/03/17 14:55:33.678181
Backup extraction complete.
INFO: 2021/03/17 14:55:33.678187 base_0000002600000C5F000000AC fetched. Upgrading from LSN c5fac000028 to LSN c606e000098
INFO: 2021/03/17 14:55:33.678242 Finished decompression of pg_control.tar.br
INFO: 2021/03/17 14:55:34.397638 Finished extraction of part_001.tar.br
ERROR: 2021/03/17 14:55:34.397674 Extraction error in part_001.tar.br: extractOne: Interpret failed: Interpret: failed to create symlink back/postgresql.auto.conf: symlink /postgresql.auto.conf back/postgresql.auto.conf: file exists
INFO: 2021/03/17 14:55:34.397685 Finished decompression of part_001.tar.br
ERROR: 2021/03/17 14:55:34.397715 part_001.tar.br DecryptAndDecompressTar: br decompress failed. Is archive encrypted?: io: read/write on closed pipe
INFO: 2021/03/17 14:55:35.434524 Finished decompression of part_002.tar.br
INFO: 2021/03/17 14:55:35.434563 Finished extraction of part_002.tar.br
INFO: 2021/03/17 14:55:36.724300 Finished decompression of part_003.tar.br
INFO: 2021/03/17 14:55:36.724326 Finished extraction of part_003.tar.br
INFO: 2021/03/17 14:55:39.742312 Finished decompression of part_004.tar.br
INFO: 2021/03/17 14:55:39.742338 Finished extraction of part_004.tar.br
INFO: 2021/03/17 14:55:39.788014 Finished decompression of part_006.tar.br
INFO: 2021/03/17 14:55:39.788032 Finished extraction of part_006.tar.br
INFO: 2021/03/17 14:56:40.552359 Finished extraction of part_001.tar.br
ERROR: 2021/03/17 14:56:40.552402 Extraction error in part_001.tar.br: extractOne: Interpret failed: Interpret: failed to create symlink back/postgresql.auto.conf: symlink /postgresql.auto.conf back/postgresql.auto.conf: file exists
INFO: 2021/03/17 14:56:40.552424 Finished decompression of part_001.tar.br
ERROR: 2021/03/17 14:56:40.552457 part_001.tar.br DecryptAndDecompressTar: br decompress failed. Is archive encrypted?: io: read/write on closed pipe
ERROR: 2021/03/17 14:56:40.552460 Failed to fetch backup: failed to extract files:
part_001.tar.br

Seems like the problem is with symlink of postgresql.auto.conf archived from Stolon:

 postgresql.auto.conf -> /postgresql.auto.conf

[x4m]

Thanks for reporting! Looks like a bug in symlink handling...

[lexasoft123]

@x4m any news here?

[x4m]

There was a related fix #1057, but not exactly this one, sorry. A PR would be welcomed.

[sebasmannem]

I will issue a PR