JetBackup 5 users may run into an issue when running backups to an S3 destination where the following error is encountered:
[ERROR] Failed uploading file '/home/exampleaccount/mail/example.com/exam/cur/example.file'. Error: Empty reply from server (cURL Error Code: 52)
When encountering this error, checking journalctl -u jetbackup5d may indicate an issue with input/output errors:
Notice: fread(): Read of 8192 bytes failed with errno=5 Input/output error in /usr/local/jetapps/var/lib/jetbackup5/Core/Destination/S3/Client/File/FileStream.inc on line 54
The underlying issue here may be corruption in the disk. To verify this, you can attempt to read one of these files using cat:
v9jNVH/ZzZP/2s3Tv9vOEz/dDlL/3k6Sv9+Okr/fjpK/346Sv9+Okr/fjpK/346Sv9+Okr/fjpK /346Sv9+Okcat: /home/exampleaccount/mail/example.com/exam/cur/example.file
: Input/output error
Receiving the aforementioned response when attempting to read the file further indicates an issue with corruption. This can be confirmed using dmesg -w :
[71969546.045326] megaraid_sas 0000:02:00.0: 474278 (766180824s/0x0002/FATAL) - Unrecoverable medium error during recovery on PD 01(e0x20/s1) at 2d62dc70
[71969546.050291] megaraid_sas 0000:02:00.0: 474279 (766180824s/0x0001/FATAL) - VD bad block table on VD 00/0 is full; unable to log block 5ac5b870 (on PD 00(e0x20/s0) at 2d62dc70)
[71969546.053208] sd 0:2:0:0: [sda] tag#0 FAILED Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK cmd_age=2s
[71969546.053224] sd 0:2:0:0: [sda] tag#0 CDB: Read(10) 28 00 5a c5 b8 70 00 00 08 00
[71969546.053228] blk_update_request: I/O error, dev sda, sector 1522907248
These messages indicate corruption or an issue with the disk preventing JetBackup from properly reading the files as necessary when creating a backup.
Fortunately, it's important to note, that a partially completed status does not indicate the entire backup failed. This backup may be marked as DAMAGED in the JetBackup GUI but items that were able to successfully complete are still accessible for restores.