Prior to 2.16 the Perl manifest code would skip any file that began with a dot. This was not intentional but it allowed PostgreSQL socket files to be located in the data directory. The new C code in 2.16 did not have this unintentional exclusion so socket files in the data directory caused errors.
Worse, the file type error was being thrown before the exclusion check so there was really no way around the issue except to move the socket files out of the data directory.
Special file types (e.g. socket, pipe) will now be automatically skipped and a warning logged to notify the user of the exclusion. The warning can be suppressed with an explicit --exclude.
Reported by CluelessTechnologist, Janis Puris, Rachid Broum.
Putting the checksum at the beginning of the file made it impossible to stream the file out when saving. The entire file had to be held in memory while it was checksummed so the checksum could be written at the beginning.
Instead place the checksum at the end. This does not break the existing Perl or C code since the read is not order dependent.
There are no plans to improve the Perl code to take advantage of this change, but it will make the C implementation more efficient.
Reviewed by Cynthia Shang.
The log directories/files were being created with a mix of modes depending on whether they were created in C or Perl. In particular, the C code was creating log files with the execute bit set for the user and group which was just odd.
Standardize on 750/640 for both code paths.
Suggested by Damiano Albani.
The Perl versions remain because they are still being used by the Perl stanza commands. Once the stanza commands are migrated they can be removed.
Contributed by Cynthia Shang.
Bug Fixes:
* Retry S3 RequestTimeTooSkewed errors instead of immediately terminating. (Reported by sean0101n, Tim Garton, Jesper St John, Aleš Zelený.)
* Fix incorrect handling of transfer-encoding response to HEAD request. (Reported by Pavel Suderevsky.)
* Fix scoping violations exposed by optimizations in gcc 9. (Reported by Christian Lange, Ned T. Crigler.)
Features:
* Add repo-s3-port option for setting a non-standard S3 service port.
Improvements:
* The local command for backup is implemented entirely in C. (Contributed by David Steele, Cynthia Shang.)
* The check command is implemented partly in C. (Reviewed by Cynthia Shang.)
Implement switch WAL and archive check in C but leave the rest in Perl for now.
The main idea was to have some real integration tests for the new database code so the rest of the migration can wait.
Reviewed by Cynthia Shang.
If this option is set then ports appended to repo-s3-endpoint or repo-s3-host will be ignored.
Setting this option explicitly may be the only way to use a bare ipv6 address with S3 (since multiple colons confuse the parser) but we plan to improve this in the future.
The local process is now entirely migrated to C. Since all major I/O operations are performed in the local process, the vast majority of I/O is now performed in C.
Contributed by David Steele, Cynthia Shang.
For offline backups the upper bound was being set to 0x0000FFFF0000FFFF rather than UINT64_MAX. This meant that page checksum errors might be ignored for databases with a lot of past WAL in offline mode.
Online mode is not affected since the upper bound is retrieved from pg_start_backup().
Since 2.91 JSON::PP has a bias for saving variables that look like numbers as numbers even if they were declared as strings.
Force versions to strings where needed by appending ''.
Update the json-pp-perl package on Ubuntu 18.04 to 2.97 to provide test coverage.
No new Perl code is being developed, so these tools are just taking up time and making migrations to newer platforms harder. There are only a few Perl tests remaining with full coverage so the coverage tool does not warn of loss of coverage in most cases.
Remove both tools and associated libraries.
Maintaining the storage layer/drivers in two languages is burdensome. Since the integration tests require the Perl storage layer/drivers we'll need them even after the core code is migrated to C. Create an interface layer so the Perl code can be removed and new storage drivers/features introduced without adding Perl equivalents.
The goal is to move the integration tests to C so this interface will eventually be removed. That being the case, the interface was designed for maximum compatibility to ease the transition. The result looks a bit hacky but we'll improve it as needed until it can be retired.
Bug Fixes:
* Fix archive retention expiring too aggressively. (Fixed by Cynthia Shang. Reported by Mohamad El-Rifai.)
Improvements:
* The expire command is implemented entirely in C. (Contributed by Cynthia Shang.)
* The local command for restore is implemented entirely in C.
* Remove hard-coded PostgreSQL user so $PGUSER works. (Suggested by Julian Zhang, Janis Puris.)
* Honor configure --prefix option. (Suggested by Daniel Westermann.)
* Rename repo-s3-verify-ssl option to repo-s3-verify-tls. The new name is preferred because pgBackRest does not support any SSL protocol versions (they are all considered to be insecure). The old name will continue to be accepted.
Documentation Improvements:
* Add FAQ to the documentation. (Contributed by Cynthia Shang.)
* Use wal_level=replica in the documentation for PostgreSQL ≥ 9.6. (Suggested by Patrick McLaughlin.)
This implementation duplicates the functionality of the Perl code but does so with different logic and includes full unit tests.
Along the way at least one bug was fixed, see issue #748.
Contributed by Cynthia Shang.
The PostgreSQL user was hard-coded to the OS user which libpq will automatically use if $PGUSER is not set, so this code was redundant and prevented $PGUSER from working when set.
Suggested by Julian Zhang, Janis Puris.
This was not enforced at parse time because repo1-cipher-type could be passed on the command-line even in cases where encryption was not needed by the subprocess.
Filter repo-cipher-type so it is never passed on the command line. If the subprocess does not have access to the passphrase then knowing the encryption type is useless anyway.
Allows listing repo paths/files from the command-line, to be used primarily for testing and debugging.
This command is internal-only so the interface may change at any time without notice.
The new name is preferred because pgBackRest does not support any SSL protocol versions (they are all considered to be insecure).
The old name will continue to be accepted.
This is just the part of restore run by the local helper processes, not the entire command.
Even so, various optimizations in the code (like pipelining and optimizations for zero-length files) should make the restore command faster on object stores.
Bug Fixes:
* Fix segfault when process-max > 8 for archive-push/archive-get. (Reported by Jens Wilke.)
Improvements:
* Bypass database checks when stanza-delete issued with force. (Contributed by Cynthia Shang. Suggested by hatifnatt.)
* Add configure script for improved multi-platform support.
Documentation Features:
* Add user guides for CentOS/RHEL 6/7.
The rules for when a C remote is required are getting complicated and will get worse when restoreFile() is migrated.
Instead, set the --c option when a C remote is required. This option will be removed when the remote is entirely implemented in C.
Remove "File" and "Driver" from object names so they are shorter and easier to keep consistent.
Also remove the "driver" directory so storage implementations are visible directly under "storage".
Bug Fixes:
* Fix zero-length reads causing problems for IO filters that did not expect them. (Reported by brunre01, jwpit, Tomasz Kontusz, guruguruguru.)
* Fix reliability of error reporting from local/remote processes.
* Fix Posix/CIFS error messages reporting the wrong filename on write/sync/close.
IMPORTANT NOTE: The new TLS/SSL implementation forbids dots in S3 bucket names per RFC-2818. This security fix is required for compliant hostname verification.
Bug Fixes:
* Fix issues when a path option is / terminated. (Reported by Marc Cousin.)
* Fix issues when log-level-file=off is set for the archive-get command. (Reported by Brad Nicholson.)
* Fix C code to recognize host:port option format like Perl does. (Reported by Kyle Nevins.)
* Fix issues with remote/local command logging options.
Improvements:
* The archive-push command is implemented entirely in C.
* Increase process-max limit to 999. (Suggested by Rakshitha-BR.)
* Improve error message when an S3 bucket name contains dots.
Documentation Improvements:
* Clarify that S3-compatible object stores are supported. (Suggested by Magnus Hagander.)
This new implementation should behave exactly like the old Perl code with the exception of updated log messages.
Remove as much of the Perl code as possible without breaking other commands.
This condition was not being properly checked for in the C code and it caused problems in the info command, at the very least.
Instead of applying a local fix, introduce a new path option type that will rigorously check the format of any incoming paths.
Reported by Marc Cousin.
This command was previously forked off from the archive-push command which required a bit of artificial option and log manipulation.
A separate command is easier to test and will work on platforms that don't have fork(), e.g. Windows.
Bug Fixes:
* Fix possible truncated WAL segments when an error occurs mid-write. (Reported by blogh.)
* Fix info command missing WAL min/max when stanza specified. (Fixed by Stefan Fercot.)
* Fix non-compliant JSON for options passed from C to Perl. (Reported by Leo Khomenko.)
Improvements:
* The archive-get command is implemented entirely in C.
* Enable socket keep-alive on older Perl versions. (Contributed by Marc Cousin.)
* Error when parameters are passed to a command that does not accept parameters. (Suggested by Jason O'Donnell.)
* Add hints when unable to find a WAL segment in the archive. (Suggested by Hans-Jürgen Schönig.)
* Improve error when hostname cannot be found in a certificate. (Suggested by James Badger.)
* Add additional options to backup.manifest for debugging purposes. (Contributed by blogh.)
Add the buffer-size, compress-level, compress-level-network, and process-max options to the backup:option section in backup.manifest to aid in debugging.
It may also make sense to propagate these options up to backup.info so they can be displayed in the info command, but for now this is deemed sufficient.
Contributed by blogh.
When this error happens in the context of a backup it can be a bit mystifying as to why the backup is failing. Add some hints to get the user started.
These hints will appear any time a WAL segment can't be found, which makes the hint about the check command redundant when the user is actually running the check command, but it doesn't seem worth trying to exclude the hint in that case.
Suggested by Hans-Jürgen Schönig.
The prior method depended on IO:Socket:SSL to push the keep-alive options down to the socket but it only worked for recent versions of the module.
Instead, create the socket directly using IO::Socket::IP if available or IO:Socket:INET as a fallback. The keep-alive option is set directly on the socket before it is passed to IO:Socket:SSL.
Contributed by Marc Cousin.
This new implementation should behave exactly like the old Perl code with the exception of a few updated log messages.
Remove as much of the Perl code as possible without breaking other commands.
We have been using a hacked-up JSON generator to pass options from C to Perl since the C binary was introduced. This generator was not very compliant which led to issues with \n, ", etc. inside strings.
We have a fully-compliant JSON generator now so use that instead.
Reported by Leo Khomenko.
This command was previously forked off from the archive-get command which required a bit of artificial option and log manipulation.
A separate command is easier to test and will work on platforms that don't have fork(), e.g. Windows.
The file write object destructors called close() and finalized the file even if it was not completely written. This was an issue in both the C and Perl code.
Rewrite the destructors to simply free resources (like file handles) rather than calling the close() method. This leaves the temp file in place for filesystems that use temp files.
Add unit tests to prevent regression.
Reported by blogh.
The check to verify that pg-path and data_directory are equal was not working because pg-path was getting overwritten with data_directory before validation took place.
Reported by James Chanco Jr.
Bug Fixes:
* Fix issue with multiple async status files causing a hard error. (Reported by Vidhya Gurumoorthi, Joe Ayers, Douglas J Hunley.)
Improvements:
* The info command is implemented entirely in C.
* Simplify info command text message when no stanzas are present by replacing the repository path with "the repository".
* Add _DARWIN_C_SOURCE flag to Makefile for MacOS builds. (Contributed by Douglas J Hunley.)
* Update address lookup in C TLS client to use modern methods. (Suggested by Bruno Friedmann.)
* Include Posix-compliant header for strcasecmp() and fd_set. (Suggested by ucando.)
Multiple status files were being created by asynchronous archiving if a high-level error occurred after one or more WAL segments had already been transferred successfully. Error files were being written for every file in the queue regardless of whether it had already succeeded. To fix this, add an option to skip writing error files when an ok file already exists.
There are other situations where both files might exist (various fsync and filesystem error scenarios) so it seems best to retry in the case that multiple status files are found rather than throwing a hard error (which then means that archiving is completely stuck). In the case of multiple status files, a warning will be logged to alert the user that something unusual is happening and the command will be retried.
Reported by fpa-postgres, Joe Ayers, Douglas J Hunley.
The C info code has already been committed but this commit wires it into main.
Also remove the info Perl code and tests since they are no longer called.
Executes a child process and allows the calling process to communicate with it using read/write io.
This object is specially tailored to implement the protocol layer and may or may not be generally applicable to general purpose
execution.
Replace the repository path with just "the repository". The path is not important in this context and it is clearer to state where the stanzas are missing from.
The Perl code has a tendency to generate absolute paths even when they are not needed. This change helps the C and Perl storage work together via the protocol layer.
The C storage object strives to use rules whenever possible instead of generating absolute paths. This change helps the C and Perl storage work together via the protocol layer.
Bug Fixes:
* Remove request for S3 object info directly after putting it. (Reported by Matt Kunkel.)
* Correct archive-get-queue-max to be size type. (Reported by Ronan Dunklau.)
* Add error message when current user uid/gid does not map to a name. (Reported by Camilo Aguilar.)
* Error when --target-action=shutdown specified for PostgreSQL < 9.5.
Improvements:
* Set TCP keepalives on S3 connections. (Suggested by Ronan Dunklau.)
* Reorder info command text output so most recent backup is output last. (Contributed by Cynthia Shang. Suggested by Ryan Lambert.)
* Change file ownership only when required.
* Redact authentication header when throwing S3 errors. (Suggested by Brad Nicholson.)
Keepalives may help in situations where RST packets are being blocked by a firewall or otherwise do not arrive.
The C code uses select on all reads so it should never block, but add keepalives just in case.
Suggested by Ronan Dunklau.
After a stanza-upgrade backups for the old cluster are displayed until they expire. Cluster info was output newest to oldest which meant after an upgrade the most recent backup would no longer be output last.
Update the text output ordering so the most recent backup is always output last.
Contributed by Cynthia Shang.
Suggested by Ryan Lambert.
Previously chown() would be called even when no ownership changes were required.
In most cases changes are not required and it seems better to perform an extra stat() rather than an extra chown().
Also add unit tests for owner() since there weren't any.
The authentication header contains the access key (not the secret key) so don't include it in errors that can be seen at any log level.
Suggested by Brad Nicholson.
After a file is copied during backup the size is requested from the storage in case it differs from what was written so that repo-size can be reported accurately. This is useful for situations where compression is being done by the filesystem (e.g. ZFS) and what is stored can differ in size from what was written.
In S3 the reported size will always be exactly what was written so there is no need to check the size and doing so immediately can cause problems because the new file might not appear in list commands. This has not been observed on S3 (though it seems to be possible) but it has been reported on the Swift S3 gateway.
Add a driver capability to determine if size needs to be called after a file is written and if not then simply use the number of bytes written for repo-size.
Reported by Matt Kunkel.
Bug Fixes:
* Fix issue with archive-push-queue-max not being honored on connection error. (Reported by Lardière Sébastien.)
* Fix static WAL segment size used to determine if archive-push-queue-max has been exceeded.
* Fix error after log file open failure when processing should continue. (Reported by vthriller.)
Features:
* Automatically enable backup checksum delta when anomalies (e.g. timeline switch) are detected. (Contributed by Cynthia Shang.)
Improvements:
* Retry all S3 5xx errors rather than just 500 internal errors. (Suggested by Craig A. James.)
There are a number of cases where a checksum delta is more appropriate than the default time-based delta:
* Timeline has switched since the prior backup
* File timestamp is older than recorded in the prior backup
* File size changed but timestamp did not
* File timestamp is in the future compared to the start of the backup
* Online option has changed since the prior backup
A practical example is that checksum delta will be enabled after a failover to standby due to the timeline switch. In this case, timestamps can't be trusted and our recommendation has been to run a full backup, which can impact the retention schedule and requires manual intervention.
Now, a checksum delta will be performed if the backup type is incr/diff. This means more CPU will be used during the backup but the backup size will be smaller and the retention schedule will not be impacted.
Contributed by Cynthia Shang.
We were already retrying 500 errors but 503 (rate-limiting) errors were not being retried and would cause an instant failure which aborted the command.
There are only two 5xx errors currently implemented by S3 but instead of adding 503 simply retry all 5xx errors. This is consistent with the http definition of this error class, "the server failed to fulfill an apparently valid request."
Suggested by Craig A. James.
This calculation was missed when the WAL segment size was made dynamic in preparation for PostgreSQL 11.
Fix the calculation by checking the actual WAL file sizes instead of using an estimate based on WAL segment size. This is more accurate because it takes into account .history and .backup files, which are smaller. Since the calculation is done in the async process the additional processing time should not adversely affect performance.
Remove the PG_WAL_SIZE constant and instead use local constants where the old value is still required. This is only the case for some tests and PostgreSQL 8.3 which does not provide a way to get the WAL segment size from pg_control.
If an error occurred while acquiring a lock on a remote server the error would be reported correctly, but the queue max detection code was not reached. The tests failed to detect this because they fixed the connection before queue max, allowing the ccde to be reached.
Move the queue max code before the lock so it will run even when remote connections are not working. This means that no attempt will be made to transfer WAL once queue max has been exceeded, but it makes it much more likely that the code will be reach without error.
Update tests to continue errors up to the point where queue max is exceeded.
Reported by Lardière Sébastien.
Bug Fixes:
* Fix missing missing URI encoding in S3 driver. (Reported by Dan Farrell.)
* Fix incorrect error message for duplicate options in configuration files. (Reported by Jesper St John.)
* Fix incorrectly reported error return in info logging. A return code of 1 from the archive-get was being logged as an error message at info level but otherwise worked correctly.
Features:
* Add checksum delta for incremental backups which uses checksums rather than timestamps to determine if files have changed. (Contributed by Cynthia Shang.)
* PostgreSQL 11 support, including configurable WAL segment size.
Improvements:
* Ignore all files in a linked tablespace directory except the subdirectory for the current version of PostgreSQL. Previously an error would be generated if other files were present and not owned by the PostgreSQL user.
* Improve info command to display the stanza cipher type. (Contributed by Cynthia Shang. Suggested by Douglas J Hunley.)
* Improve support for special characters in filenames.
* Allow delta option to be specified in the pgBackRest configuration file. (Contributed by Cynthia Shang.)
PostgreSQL 11 introduces configurable WAL segment sizes, from 1MB to 1GB.
There are two areas that needed to be updated to support this: building the archive-get queue and checking that WAL has been archived after a backup. Both operations require the WAL segment size to properly build a list.
Checking the archive after a backup is still implemented in Perl and has an active database connection, so just get the WAL segment size from the database.
The archive-get command does not have a connection to the database, so get the WAL segment size from pg_control instead. This requires a deeper inspection of pg_control than has been done in the past, so it seemed best to copy the relevant data structures from each version of PostgreSQL and build a generic interface layer to address them. While this approach is a bit verbose, it has the advantage of being relatively simple, and can easily be updated for new versions of PostgreSQL.
Since the integration tests generate pg_control files for testing, teach Perl how to generate files with the correct offsets for both 32-bit and 64-bit architectures.
Use checksums rather than timestamps to determine if files have changed. This is useful in cases where the timestamps may not be trustworthy, e.g. when performing an incremental after failing over to a standby.
If checksum delta is enabled then checksums will be used for verification of resumed backups, even if they are full. Resumes have always used checksums to verify the files in the repository, enabling delta performs checksums on the database files as well.
Note that the user must manually enable this feature in cases were it would be useful or just keep in enabled all the time. A future commit will address automatically enabling the feature in cases where it seems likely to be useful.
Contributed by Cynthia Shang.
Apparently we never needed to run this function remotely.
It will be needed by the backup checksum delta feature, so implement it now.
Contributed by Cynthia Shang.
The test to make sure that some files (e.g. pg_control) do not get removed during the backup was lost during the storage refactor committed at de7fc37f.
This did not impact the integrity of the backups, but bring it back since it is a nice sanity check.
Contributed by Cynthia Shang.
The info messages were spread around and logged differently based on the execution path and in some cases logged nothing at all.
Temporarily track the async server status with a flag so that info messages are not output in the async process. The async process will be refactored as a separate command to be exec'd in a future commit.
% characters caused issues in backup/restore due to filenames being appended directly into a format string.
Reserved XML characters (<>&') caused issues in the S3 driver due to improper escaping.
Add a file with all common special characters to regression testing.
File names with uncommon characters (e.g. @) caused authentication failures due to S3 encoding them correctly while the S3 driver did not.
Reported by Dan Farrell.
A return code of 1 from the archive-get was being logged as an error message at info level but otherwise worked correctly.
Also improve info messages when an archive segment is or is not found.
Previously an error would be generated if other files were present and not owned by the PostgreSQL user. This hasn't been a big deal in practice but it could cause issues.
Also add tests to make sure the same logic applies with links to files, i.e. all other files in the directory should be ignored. This was actually working correctly, but there were no tests for it before.
Bug Fixes:
* Fix issue where relative links in $PGDATA could be stored in the backup with the wrong path. This issue did not affect absolute links and relative tablespace links were caught by other checks. (Reported by Cynthia Shang.)
* Remove incompletely implemented online option from the check command. Offline operation runs counter to the purpose of this command, which is to check if archiving and backups are working correctly. (Reported by Jason O'Donnell.)
* Fix issue where errors raised in C were not logged when called from Perl. pgBackRest properly terminated with the correct error code but lacked an error message to aid in debugging. (Reported by Douglas J Hunley.)
* Fix issue when a boolean option (e.g. delta) was specified more than once. (Reported by Yogesh Sharma.)
Features:
* Allow any option to be set in an environment variable. This includes options that previously could only be specified on the command line, e.g. stanza, and secret options that could not be specified on the command-line, e.g. repo1-s3-key-secret.
* Exclude temporary and unlogged relation (table/index) files from backup. Implemented using the same logic as the patches adding this feature to PostgreSQL, 8694cc96 and 920a5e50. Temporary relation exclusion is enabled in PostgreSQL ≥ 9.0. Unlogged relation exclusion is enabled in PostgreSQL ≥ 9.1, where the feature was introduced. (Contributed by Cynthia Shang.)
* Allow arbitrary directories and/or files to be excluded from a backup. Misuse of this feature can lead to inconsistent backups so read the --exclude documentation carefully before using. (Reviewed by Cynthia Shang.)
* Add log-subprocess option to allow file logging for local and remote subprocesses.
* PostgreSQL 11 Beta 3 support.
Improvements:
* Allow zero-size files in backup manifest to reference a prior manifest regardless of timestamp delta. (Contributed by Cynthia Shang.)
* Improve asynchronous archive-get/archive-push performance by directly checking status files. (Contributed by Stephen Frost.)
* Improve error message when a command is missing the stanza option. (Suggested by Sarah Conway.)
The log-subprocess feature added in 22765670 failed to take into account the naming for remote processes spawned by local processes. Not only was the local command used for the naming of log files but the process id was not pass through. This meant every remote log was named "[stanza]-local-remote-000" which is confusing and meant multiple processes were writing to the same log.
Instead, pass the real command and process id to the remote. This required a minor change in locking to ignore locks if process id is greater than 0 since remotes started by locals never lock.
Relative link paths were being combined with the paths of previous links (relative or absolute) due to the $strPath variable being modified in the current iteration rather than simply being passed to the next level of recursion.
This issue did not affect absolute links and relative tablespace links were caught by other checks, though the error was confusing.
Reported by Cynthia Shang.
