# Error in xtrabackup prepare: "cannot open ./xtrabackup\_logfile" **URL:** \ **Category:** Percona XtraBackup\ **Created:** [May 7, 2025, 9:55pm UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868 "2025-05-07T21:55:51Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![toby5box](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/toby5box/32/20955_2.png) [@toby5box](https://forums.percona.com/u/toby5box)\ **Post date:** [May 7, 2025, 9:55pm UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/1 "2025-05-07T21:55:51Z")
Hi, I am testing a legacy backup system and am having problems at the prepare step. The backup is to S3, of mysql 8.0.21, using `xtrabackup version 8.0.25-17 based on MySQL server 8.0.25 Linux (x86_64) (revision id: d27028b)` The error I receive is: ```auto # xtrabackup --prepare --apply-log-only --target-dir=test-restore/ xtrabackup: recognized client arguments: --prepare=1 --apply-log-only=1 --target-dir=test-restore/ xtrabackup version 8.0.25-17 based on MySQL server 8.0.25 Linux (x86_64) (revision id: d27028b) xtrabackup: cd to /root/test-restore/ xtrabackup: This target seems to be not prepared yet. Number of pools: 1 Operating system error number 2 in a file operation. The error means the system cannot find the path specified. xtrabackup: Warning: cannot open ./xtrabackup_logfile. will try to find. Operating system error number 2 in a file operation. The error means the system cannot find the path specified. xtrabackup: Fatal error: cannot find ./xtrabackup_logfile. ``` The `xtrabackup_logfile` is indeed missing: ```auto # ls -l test-restore/xtr* -rw-r--r--. 1 root root 77 May 3 00:07 test-restore/xtrabackup_binlog_info.00000000000000000000 -rw-r--r--. 1 root root 36 May 3 00:07 test-restore/xtrabackup_binlog_info.00000000000000000001 -rw-r--r--. 1 root root 105 May 7 03:51 test-restore/xtrabackup_checkpoints -rw-r--r--. 1 root root 161 May 3 00:07 test-restore/xtrabackup_checkpoints.00000000000000000000 -rw-r--r--. 1 root root 36 May 3 00:07 test-restore/xtrabackup_checkpoints.00000000000000000001 -rw-r--r--. 1 root root 734 May 7 03:51 test-restore/xtrabackup_info -rw-r--r--. 1 root root 783 May 3 00:07 test-restore/xtrabackup_info.00000000000000000000 -rw-r--r--. 1 root root 29 May 3 00:07 test-restore/xtrabackup_info.00000000000000000001 -rw-r--r--. 1 root root 884276 May 3 00:07 test-restore/xtrabackup_logfile.00000000000000000000 -rw-r--r--. 1 root root 32 May 3 00:07 test-restore/xtrabackup_logfile.00000000000000000001 -rw-r--r--. 1 root root 95 May 3 00:07 test-restore/xtrabackup_tablespaces.00000000000000000000 -rw-r--r--. 1 root root 36 May 3 00:07 test-restore/xtrabackup_tablespaces.00000000000000000001 ``` It’s missing from all attempts to make a full backup. The command that creates this backup on S3 is: ```auto xtrabackup --backup --no-lock --stream=xbstream --target-dir="${DAILY_BACKUP_DIR}" --extra-lsndir="${DAILY_BACKUP_DIR}" \ --keyring-file-data=${KEYRING_NAME} \ --host=${DB_HOST} --port=${DB_PORT} --user=${DB_USER} --password="${DB_PASS}" \ --parallel=${NUM_THREADS} | \ xbcloud put --storage=s3 \ --s3-endpoint="${S3_ENDPOINT}" \ --s3-access-key="${S3_ACCESSKEY}" \ --s3-secret-key="${S3_SECRETKEY}" \ --s3-bucket="${S3_BUCKET}" \ --parallel=${NUM_THREADS} \ "${HOSTNAME}/${BACKUP_NAME}/full" ``` This is blocking me from preparing a backup. Specifically I am trying to prepare a base (full) backup in order to try applying incremental backups to it. This is happening on the first, base prepare. Thankyou in advance ---
**Author:** ![lalit.choudhary](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/lalit.choudhary/32/51_2.png) [@lalit.choudhary](https://forums.percona.com/u/lalit.choudhary)\ **Post date:** [May 8, 2025, 5:24am UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/2 "2025-05-08T05:24:13Z")
Hello @toby5box > [@toby5box](#): > > It’s missing from all attempts to make a full backup. Can you check full backup log ? See if it’s completed successfully without any error. ---
**Author:** ![satya.bodapati](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/satya.bodapati/32/1322_2.png) [@satya.bodapati](https://forums.percona.com/u/satya.bodapati)\ **Post date:** [May 8, 2025, 10:19am UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/3 "2025-05-08T10:19:33Z")
I think you didn’t use xbcloud to download the backup from s3. xbcloud does this splitting of files. So please use `xbcloud get <> | xbstream` and it will merge the files. You have all the files but only in format that xbcloud and xbstream understands. Please follow the steps from the documentation : [Use the xbcloud binary with Amazon S3 - Percona XtraBackup](https://docs.percona.com/percona-xtrabackup/8.0/xbcloud-s3.html#permissions-setup) ---
**Author:** ![toby5box](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/toby5box/32/20955_2.png) [@toby5box](https://forums.percona.com/u/toby5box)\ **Post date:** [May 8, 2025, 3:44pm UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/4 "2025-05-08T15:44:15Z")
The backups always complete without error. Here’s a snippet of the log: ```auto May 8 00:06:50 db1-new CROND[3973240]: (root) CMDOUT (250508 00:06:50 xbcloud: successfully uploaded chunk: db1-new/Thu-2025-05-08-00-00-02/full/ib_buffer_pool.00000000000000000000, size: 10405383) May 8 00:06:51 db1-new CROND[3973240]: (root) CMDOUT (xtrabackup: Transaction log of lsn (1643822304659) to (1643823311018) was copied.) May 8 00:06:51 db1-new CROND[3973240]: (root) CMDOUT (2025-05-08T00:06:51.419302Z 0 [Note] [MY-010733] [Server] Shutting down plugin 'keyring_file') May 8 00:06:51 db1-new CROND[3973240]: (root) CMDOUT (2025-05-08T00:06:51.419375Z 0 [Note] [MY-010733] [Server] Shutting down plugin 'daemon_keyring_proxy_plugin') May 8 00:06:51 db1-new CROND[3973240]: (root) CMDOUT (250508 00:06:51 completed OK!) May 8 00:06:52 db1-new CROND[3973240]: (root) CMDOUT (250508 00:06:52 xbcloud: Upload completed.) May 8 00:06:52 db1-new CROND[3973240]: (root) CMDOUT (Completed 105 Bytes/105 Bytes (1.4 KiB/s) with 1 file(s) remaining#015upload: ../opt/x/backup-lns-data/Thu-2025-05-08-00-00-02/xtrabackup_checkpoints to s3://x-database-backups/db1-new/Thu-2025-05-08-00-00-02/full-lsn//opt/x/backup-lns-data/Thu-2025-05-08-00-00-02/xtrabackup_checkpoints) May 8 00:06:53 db1-new CROND[3973240]: (root) CMDOUT (Completed 723 Bytes/723 Bytes (9.0 KiB/s) with 1 file(s) remaining#015upload: ../opt/x/backup-lns-data/Thu-2025-05-08-00-00-02/xtrabackup_info to s3://x-database-backups/db1-new/Thu-2025-05-08-00-00-02/full-lsn//opt/x/backup-lns-data/Thu-2025-05-08-00-00-02/xtrabackup_info) May 8 00:06:53 db1-new CROND[3973240]: (root) CMDOUT (All backup operations complete. Total elapsed time: 0:06:51) ``` ---
**Author:** ![toby5box](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/toby5box/32/20955_2.png) [@toby5box](https://forums.percona.com/u/toby5box)\ **Post date:** [May 8, 2025, 3:45pm UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/5 "2025-05-08T15:45:48Z")
Satya No, I’m using the file based backup, xbcloud, not xbstream. I believe an xbstream format backup does not have this problem, but that’s a different topic. Before switching to xbstream I want to understand why I am having this problem with xbcloud in the legacy configuration and if it is a genuine bug. (I’m also re-testing xbstream format right now as I need to be sure that we do in fact have at least one restorable backup. But I still would like to understand the problem with xbcloud.) ---
**Author:** ![toby5box](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/toby5box/32/20955_2.png) [@toby5box](https://forums.percona.com/u/toby5box)\ **Post date:** [May 8, 2025, 5:38pm UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/6 "2025-05-08T17:38:27Z")
Indeed, the xbstream format when streamed to s3 as a single object does contain the `xtrabackup_logfile`: ```auto ... performance_schema/binary_log_trans_1681.sdi performance_schema/tls_channel_stat_1682.sdi demo/db.opt mysql-bin.037583 mysql-bin.index xtrabackup_binlog_info xtrabackup_logfile xtrabackup_checkpoints ib_buffer_pool backup-my.cnf xtrabackup_info xtrabackup_tablespaces ``` This is the last few lines output of `aws s3 cp s3://x-database-backups/db1-new/2025-05-08-16-02-38/full.xbstream - |xbstream -v -x -C test-restore` And in this case, the prepare step completes successfully and I can start mysqld on the results. ---
**Author:** ![satya.bodapati](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/satya.bodapati/32/1322_2.png) [@satya.bodapati](https://forums.percona.com/u/satya.bodapati)\ **Post date:** [May 12, 2025, 9:21am UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/7 "2025-05-12T09:21:23Z")
@toby5box if you xbcloud, it will still use xbstream. observe --stream=xbstream parameter to xtrabackup. xbstream is just a format for streaming. You have used `xtrabackup --backup |xbcloud put..`. To use the backup, you HAVE to use xbcloud again. `xbcloud get | xbstream -x -C restore --parallel=8`. After this, you can do prepare. ---
**Author:** ![toby5box](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/toby5box/32/20955_2.png) [@toby5box](https://forums.percona.com/u/toby5box)\ **Post date:** [May 12, 2025, 9:21pm UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/8 "2025-05-12T21:21:34Z")
Thanks. I have tested this and it did work: ```auto xbcloud get --storage=s3 --s3-bucket="${S3_BUCKET}" --parallel=${NUM_THREADS} $S3PATH \ | xbstream -x -C $TARGET_DIR --parallel=$NUM_THREADS xtrabackup --prepare --keyring-file-data=`pwd`/mysql.keyring --no-apply-log --target-dir=$TARGET_DIR ``` Is there any reason to not to store the xbstream as a single object on S3 versus the `xbcloud` many-objects backup? It seems that the single object format (capturing the output of `xtrabackup` directly) is more efficient to download. ---
**Author:** ![toby5box](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/toby5box/32/20955_2.png) [@toby5box](https://forums.percona.com/u/toby5box)\ **Post date:** [May 14, 2025, 4:26am UTC](https://forums.percona.com/t/error-in-xtrabackup-prepare-cannot-open-xtrabackup-logfile/37868/9 "2025-05-14T04:26:43Z")
My logic was poor. It seems that the combination of multi-objects (xbcloud) and multithreading is likely to be faster to transfer. Even as much as 2x in my tests.