The speed of the archiving command is unimportant as long as it can keep up with the average rate at which your server generates WAL data. Normal operation continues even if the archiving process falls a little behind.
If archiving falls significantly behind, this will increase the amount of data that would be lost in the event of a disaster.
You are advised to monitor the archiving process to ensure that it is working as you intend. In writing your archive command, you should assume that the file names to be archived can be up to 64 characters long and can contain any combination of ASCII letters, digits, and dots.
Note that although WAL archiving will allow you to restore any modifications made to the data in your PostgreSQL database, it will not restore changes made to configuration files that is, postgresql.
You might wish to keep the configuration files in a location that will be backed up by your regular file system backup procedures. See Section The archive command is only invoked on completed WAL segments. Hence, if your server generates only little WAL traffic or has slack periods where it does so , there could be a long delay between the completion of a transaction and its safe recording in archive storage.
Note that archived files that are archived early due to a forced switch are still the same length as completely full files. Other utility functions related to WAL management are listed in Table If archiving or streaming replication were turned on during execution of one of these statements, WAL would not contain enough information for archive recovery.
Crash recovery is unaffected. It can create a base backup either as regular files or as a tar archive. It is not necessary to be concerned about the amount of time it takes to make a base backup. To make use of the backup, you will need to keep all the WAL segment files generated during and after the file system backup. To aid you in doing this, the base backup process creates a backup history file that is immediately stored into the WAL archive area.
This file is named after the first WAL segment file that you need for the file system backup. For example, if the starting WAL file is CD the backup history file will be named something like CD.
The second part of the file name stands for an exact position within the WAL file, and can ordinarily be ignored. Once you have safely archived the file system backup and the WAL segment files used during the backup as specified in the backup history file , all archived WAL segments with names numerically less are no longer needed to recover the file system backup and can be deleted.
However, you should consider keeping several backup sets to be absolutely certain that you can recover your data. The backup history file is just a small text file. If you used the label to identify the associated dump file, then the archived history file is enough to tell you which dump file to restore. Since you have to keep around all the archived WAL files back to your last base backup, the interval between base backups should usually be chosen based on how much storage you want to expend on archived WAL files.
You should also consider how long you are prepared to spend recovering, if recovery should be necessary — the system will have to replay all those WAL segments, and that could take awhile if it has been a long time since the last base backup. It is very important that these steps are executed in sequence, and that the success of a step is verified before proceeding to the next step.
One good practice is to use the full path where you intend to put the backup dump file. The file is critical to the integrity of the backup, should you need to restore from it. It does not matter which database within the cluster you connect to to issue this command.
You can ignore the result returned by the function; but if it reports an error, deal with that before proceeding. This is usually what you want, because it minimizes the impact on query processing. If you want to start the backup as soon as possible, use:.
It is neither necessary nor desirable to stop normal operation of the database while you do this. This terminates the backup mode and performs an automatic switch to the next WAL segment. The reason for the switch is to arrange for the last WAL segment file written during the backup interval to be ready to archive. Once the WAL segment files active during the backup are archived, you are done. In most cases this happens quickly, but you are advised to monitor your archive system to ensure there are no delays.
If the archive process has fallen behind because of failures of the archive command, it will keep retrying until the archive succeeds and the backup is complete. Some file system backup tools emit warnings or errors if the files they are trying to copy change while the copy proceeds. When taking a base backup of an active database, this situation is normal and not an error.
However, you need to ensure that you can distinguish complaints of this sort from real errors. For example, some versions of rsync return a separate exit code for "vanished source files" , and you can write a driver script to accept this exit code as a non-error case. Also, some versions of GNU tar return an error code indistinguishable from a fatal error if a file was truncated while tar was copying it. Fortunately, GNU tar versions 1. With GNU tar version 1.
Be certain that your backup dump includes all of the files under the database cluster directory e. If you are using tablespaces that do not reside underneath this directory, be careful to include them as well and be sure that your backup dump archives symbolic links as links, otherwise the restore will corrupt your tablespaces.
This slight adjustment is worthwhile because it reduces the risk of mistakes when restoring. You might also want to exclude postmaster. This file will of course be archived as a part of your backup dump file. In case of confusion it is therefore possible to look inside a backup dump file and determine exactly which backup session the dump file came from.
However, this file is not merely for your information; its presence and contents are critical to the proper operation of the system's recovery process. It is also possible to make a backup dump while the server is stopped. It is generally better to follow the continuous archiving procedure above. If you have the space to do so, copy the whole cluster data directory and any tablespaces to a temporary location in case you need them later.
Note that this precaution will require that you have enough free space on your system to hold two copies of your existing database. Remove all existing files and subdirectories under the cluster data directory and under the root directories of any tablespaces you are using. Restore the database files from your file system backup. Be sure that they are restored with the right ownership the database system user, not root! It is best to copy them, not move them, so you still have the unmodified files if a problem occurs and you have to start over.
Create a recovery command file recovery. Start the server. The server will go into recovery mode and proceed to read through the archived WAL files it needs.
About your question, PostgreSQL is really concerned about security and only allows local connections after it is installed, thus you have to configure it to allow remote connections. You can find more details on a previous answer or, as always, on PostgreSQL documentation.
Sorry for the comment. Now trying to get this running inside a Docker container to deploy Postgres on RPi quickly for dev purposes. I ran into one hiccup using the key. However, this worked. Thanks, the install went well, though it did ask if these packages could be installed without verification which I did. Is this normal, or should they have been authenticated somehow?
Yes, it is normal to be warned or asked by your Linux distribution when installing packages from non official places, as it is in this case where you are installing the packages that we have uploaded to Dropbox.
These packages are not officially recognized by Raspbian, or course. For security reasons your system has to ask you if you are sure on installing them, so it is always up to you on these cases and the recommendation is to only do the installation when you are completely sure that the packages are safe. We are in the process of creating our own repository with security keys, which will avoid these kind of warnings on your system.
I am actually trying to install the postgresql-client on raspbian so that I can connect the raspberry pi to a Windows Server box that is running the Postgres Server and display data from the Windows Server on the Raspberry through PHP auto refreshed website showing database information.
So that I can retrieve data from the database located on the Windows Server and display this data on a Kiosk that is powered by my Raspberry Pi 2 running raspbian jessie. I have been completely unsuccessful in my attempts at this project. I know it is possible as I have seen it done somewhere else. I cannot get the psql client to connect to server. I cannot configure odbc. Other sites refer to drivers named libodbcpsql. When I try and connect, it will either throw an error or nothing at all.
When the nothing happens, no one on my network can access the database until I kill the command on the raspberry, then the database performs normal immediately following the kill command. I have to reboot wheezy to finally kill the connection attempt. Jessie will let me break the connection attempt with Control-C. But even though both install packages have directories labeled PSQL, they are in fact not compatible with each other. Thanks for getting back, Paul.
I was actually trying to figure out your problem, but now everything makes sense. Unfortunately I cannot help you with Pervasive, but if you start on some PostgreSQL projects feel free to send your questions. Pingback: Compiling Postgis 2. I followed each step carefully and the result is this:. E: Child process failed. Hi Johan. What is this test you are doing? Are you running this after the PostgreSQL compilation and installation process has been complete?
Are you doing this on a fresh Raspbian Jessie install? Have in mind that the procedure listed on this post is for compiling and installing PostgreSQL 9. To answer your question, if you have PostgreSQL already installed and working on your Raspberry Pi, the error that you have reported is not suppose to affect your db, as nothing has been reinstalled, apparently.
Hi there, I installed postgresql 9. Short version: I need to compile some native extensions and the ruby gem install program for pg 0. Apparently I need header files from the development version. Could you advise me on how to proceed? Thanks so much! Y for building a server-side extension or libpq-dev for building a client-side application.
You need to install postgresql-server-dev-X. Check the mkmf. You may need configuration options. The compile ran at a good clip. I was able to see the module names. Thanks Rubens! Wooow I would like to try install Postgis extension. Any ideia? Thanks for the instructions. Download PostgreSQL v9. Your email address will not be published. Thanks Cansher for the comment. Did you compiled the packages as root? Or created a non root user? Tell me if you are having any problems to install the packages.
Thanks so much for putting 9. Hi there, Thanks for this tut. The following information may help to resolve the situation: The following packages have unmet dependencies: postgresql Thank you. Below is the script that will start a PostgreSQL server and clicking the enter key will shut the service down. This is one we were using as part of a self-contained devleopment kit running PostgreSQL 9. We chose to run on a non-standard port so we know its 9. To initialize the database for the first time, you will want to run the remarked out initdb line.
You only need to run once. From then on you can carry the server on USB device if you want and launch as you wish. Clicking enter in the window will shut it down. The assumpution of the script is that its in the root of your unzipped PostgreSQL folder.
Thursday, August Get binaries for Windows. Make sure to choose the zip archive. Next copy the below batch file into the root of the postgresql folder For first time use, unremark out the initdb step Run the batch file Below is the script that will start a PostgreSQL server and clicking the enter key will shut the service down.
Better solution. Posted by Leo Hsu and Regina Obe in 8. Trackback specific URI for this entry. Weblog: www. Weblog: webdevon. Display comments as Linear Threaded.
Thomas, Thanks for the tip. We'll correct. Could you please help me start postgresql without installing it. I have read the post but I didn't understand how to make the batch file. Sergey, You copy the contents of that script above into notepad or text editor you choose.
Then you save the file with a. Then double-click on the. Hi I'm a bit of a nube when it comes to postgresql. I'm struggling a bit to get the script to run Here's what i did. Originally i tried following your directions to the letter, so I dowlnoaded the binaries, and I made a bat file and copied the updated script into it and uncommented the necessary line. I ran the script and it complained a bit.
So I removed the extra slashes and continued. I also created bin and data directories. It still complains that it cant find the path specified for the log file. I was wondering if I'm supposed to create the log file separately and point the script at it somehow? It looks like this is the only part that doesn't work but i would really like a log file.
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