LinuxQuestions.org - Web Server Redundancy Help

Not sure about rsync and stuff, but I've done something similar with two servers with a very simple PHP script I wrote.

What basically happens is there is a cronjob (i. e. something that executes regularly every 24 hours) on the primary server that tars and bzips all important directories, calls mysqldump to dump the mysql databases, and then FTPs all this over to the secondary machine.

The idea being, if the primary goes down, I can have the center admins switch to the backup almost immediately (they'll just need to forward the traffic from the "old" IP to the new one) until a DNS update can propagate to relink the symbolic addresses with the "new" IP address. (Preferably I'd have them fix whatever went blooey on the primary system, then get it back as soon as possible to maintain redundancy).

Here's more or less what the bash script looks like that archives all the important stuff up and then dumps the vital tables from mysql:

Code:

mysqldump --set-variable=max_allowed_packet=4M --add-drop-table -uuser -ppass -hserver.com dbname > fwf_db_backup.sql



bzip2 /usr/home/fwfunn/fwf_db_backup.sql



mv /usr/home/fwfunn/fwf_db_backup.sql.bz2 public_html/backup_export/.



tar cvf fwf_files_backup_1.tar /usr/home/fwfunn/public_html/downloads/dynamic/*



bzip2 /usr/home/fwfunn/fwf_files_backup_1.tar



mv /usr/home/fwfunn/fwf_files_backup_1.tar.bz2 public_html/backup_export/.



tar cvf fwf_files_backup_2.tar /usr/home/fwfunn/public_html/images/dynamic/*



bzip2 /usr/home/fwfunn/fwf_files_backup_2.tar



mv /usr/home/fwfunn/fwf_files_backup_2.tar.bz2 public_html/backup_export/.



/home/httpd/cgi-bin/php5 /usr/home/fwfunn/public_html/send_backups.php

The last line above calls the php script that FTPs the files created above over to the secondary:

Code:

<?php

include 'cms/class.phpmailer.php';



$ftp_server = "backupserver.com";



if (($conn_id = ftp_connect($ftp_server)))

  {

    if (($login_result = ftp_login($conn_id,"username","pass")))

      {

        $file = "backup_export/fwf_db_backup.sql.bz2";

        $file_2 = "backup_export/fwf_files_backup_1.tar.bz2";

        $file_3 = "backup_export/fwf_files_backup_2.tar.bz2";



        if (ftp_put($conn_id,"public_html/auto_backups/" . basename($file),$file,FTP_BINARY))

          {

            if (ftp_put($conn_id,"public_html/auto_backups/" . basename($file_2),$file_2,FTP_BINARY))

              {

                if (ftp_put($conn_id,"public_html/auto_backups/" . basename($file_3),$file_3,FTP_BINARY))

                  {

                    ftp_close($conn_id);



                    $mail = new PHPMailer();



                    $mail->From = "";



                    $mail->FromName = "FWF Backup Script";



                    $mail->AddAddress("user@somewhere.com");



                    $mail->Subject = "FWF Backup Script Success";



                    $msg = "fwf.co.za/backup_export/fwf_db_backup.sql.bz2 transferred succesfully to backup.com/auto_backups/fwf_db_backup.sql.bz2.\n\n";



                    $msg .= "fwf.co.za/backup_export/fwf_files_backup_1.sql.bz2 transferred succesfully to backup.com/auto_backups/fwf_files_backup_1.sql.bz2.\n\n";



                    $msg .= "fwf.co.za/backup_export/fwf_files_backup_2.sql.bz2 transferred succesfully to backup.com/auto_backups/fwf_files_backup_2.sql.bz2.\n\n";



                    $mail->Body = $msg;



                    if (!$mail->Send())

                      {

                        echo "Backup script success email message cannot be sent.";

                      }

                  }



                else



                  {

                    $mail = new PHPMailer();



                    $mail->From = "";



                    $mail->FromName = "FWF Backup Script";



                    $mail->AddAddress("user@somewhere.com");



                    $mail->Subject = "FWF Backup Script Failure - File 2";



                    $mail->Body = "Failed during FWF file 2 transfer to backup.com, after successful connect and login!";



                    if (!$mail->Send())

                      {

                        echo "Backup script FWF file transfer failure email message cannot be sent.";

                      }

                  }

              }



            else



              {

                $mail = new PHPMailer();



                $mail->From = "";



                $mail->FromName = "FWF Backup Script";



                $mail->AddAddress("user@somewhere.com");



                $mail->Subject = "FWF Backup Script Failure - Files 1";



                $mail->Body = "Failed during FWF file 1 transfer to backup.com, after successful connect and login!";



                if (!$mail->Send())

                  {

                    echo "Backup script FWF file transfer failure email message cannot be sent.";

                  }

              }

          }



        else



          {

            $mail = new PHPMailer();



            $mail->From = "";



            $mail->FromName = "FWF Backup Script";



            $mail->AddAddress("user@somewhere.com");



            $mail->Subject = "FWF Backup Script Failure - DB";



            $mail->Body = "Failed during DB transfer to backup.com, after successful connect and login!";



            if (!$mail->Send())

              {

                echo "Backup script DB transfer failure email message cannot be sent.";

              }

          }

      }



    else



      {

        $mail = new PHPMailer();



        $mail->From = "";



        $mail->FromName = "FWF Backup Script";



        $mail->AddAddress("user@somewhere.com");



        $mail->Subject = "FWF Backup Script Failure";



        $mail->Body = "Failed during login to backup.com, after successful connect!";



        if (!$mail->Send())

          {

            echo "Backup script login failure email message cannot be sent.";

          }

      }

  }



 else



  {

    $mail = new PHPMailer();



    $mail->From = "";



    $mail->FromName = "FWF Backup Script";



    $mail->AddAddress("user@somewhere.com");



    $mail->Subject = "FWF Backup Script Failure";



    $mail->Body = "Failed during connect to backup.com!";



    if (!$mail->Send())

      {

        echo "Backup script connect failure email message cannot be sent.";

      }

  }

?>

Hope this helps...