Backups not completing

Since mid-December my weekly Backwpup backup is failing to complete, usually with 2 or 3 errors and warnings. Two completed on 24 & 31 December but all others have failed.

The problem seems to be with zipping the archive. Backups usually take between 1500 to 2000 seconds, but these failed runs are taking 6000 to 12000 before giving up.

Here is the log of one of the failures :-

[INFO] BackWPup 3.4.4; A project of Inpsyde GmbH
[INFO] WordPress 4.9.1 on http://markwebber.org.uk/archive/
[INFO] Log Level: Normal
[INFO] BackWPup job: New Backup
[INFO] Logfile is: backwpup_log_c8fff0_2018-01-14_03-00-01.html
[INFO] Backup file is: backwpup_ZPEP74EZ01_8a4e3f0_2018-01-14_03-00-01.zip
[14-Jan-2018 03:00:01] 1. Try to backup database …
[14-Jan-2018 03:00:01] Connected to database markwebb_wrdp1 on localhost
[14-Jan-2018 03:00:28] Added database dump “markwebb_wrdp1.sql” with 28.02 MB to backup file list
[14-Jan-2018 03:00:28] Database backup done!
[14-Jan-2018 03:00:28] 1. Trying to make a list of folders to back up …
[14-Jan-2018 03:00:31] Added “wp-config.php” to backup file list
[14-Jan-2018 03:00:31] 319 folders to backup.
[14-Jan-2018 03:00:31] 1. Trying to generate a file with installed plugin names …
[14-Jan-2018 03:00:31] Added plugin list file “Mark-Webber.pluginlist.2018-01-14.txt” with 4.47 KB to backup file list.
[14-Jan-2018 03:00:31] 1. Trying to generate a manifest file …
[14-Jan-2018 03:00:31] Added manifest.json file with 5.84 KB to backup file list.
[14-Jan-2018 03:00:31] 1. Trying to create backup archive …
[14-Jan-2018 03:00:31] Compressing files as ZipArchive. Please be patient, this may take a moment.
[14-Jan-2018 04:03:03] WARNING: Job restarts due to inactivity for more than 5 minutes.
[14-Jan-2018 04:03:04] 2. Trying to create backup archive …
[14-Jan-2018 04:09:17] WARNING: Job restarts due to inactivity for more than 5 minutes.
[14-Jan-2018 04:09:20] 2. Trying to create backup archive …
[14-Jan-2018 04:29:17] WARNING: Job restarts due to inactivity for more than 5 minutes.
[14-Jan-2018 04:29:30] 3. Trying to create backup archive …
[14-Jan-2018 05:04:11] WARNING: Job restarts due to inactivity for more than 5 minutes.
[14-Jan-2018 05:04:48] 3. Trying to create backup archive …
[14-Jan-2018 05:19:16] WARNING: Job restarts due to inactivity for more than 5 minutes.
[14-Jan-2018 05:19:31] ERROR: Step aborted: too many attempts!
[14-Jan-2018 05:19:39] 1. Try to send backup file to Dropbox …
[14-Jan-2018 05:20:07] Authenticated with Dropbox of user: Mark Webber
[14-Jan-2018 05:20:10] Uploading to Dropbox …
[14-Jan-2018 05:20:34] One old log deleted
[14-Jan-2018 05:20:34] ERROR: Job has ended with errors in 8433 seconds. You must resolve the errors for correct execution.
[14-Jan-2018 05:34:46] WARNING: ZipArchive::close(): Renaming temporary file failed: No such file or directory
[14-Jan-2018 05:34:46] ERROR: Aborted by user!
[14-Jan-2018 05:34:49] ERROR: Job has ended with errors in 9288 seconds. You must resolve the errors for correct execution.
[14-Jan-2018 05:35:55] WARNING: ZipArchive::close(): Renaming temporary file failed: No such file or directory
[14-Jan-2018 05:35:56] ERROR: Aborted by user!
[14-Jan-2018 05:35:56] ERROR: Job has ended with errors in 9355 seconds. You must resolve the errors for correct execution.
[14-Jan-2018 05:35:56] WARNING: ZipArchive::close(): Renaming temporary file failed: No such file or directory
[14-Jan-2018 05:36:00] ERROR: Aborted by user!
[14-Jan-2018 05:36:00] ERROR: Job has ended with errors in 9359 seconds. You must resolve the errors for correct execution.
[14-Jan-2018 05:40:39] WARNING: ZipArchive::close(): Renaming temporary file failed: No such file or directory
[14-Jan-2018 05:40:41] ERROR: Aborted by user!
[14-Jan-2018 05:40:41] ERROR: Job has ended with errors in 9640 seconds. You must resolve the errors for correct execution.
[14-Jan-2018 05:40:59] WARNING: ZipArchive::close(): Renaming temporary file failed: No such file or directory
[14-Jan-2018 05:40:59] ERROR: Aborted by user!
[14-Jan-2018 05:40:59] ERROR: Job has ended with errors in 9658 seconds. You must resolve the errors for correct execution.

DEBUG INFO

WordPress version: 4.9.1
BackWPup version: 3.4.4
PHP version: 7.0.27 (64bit)
MySQL version: 10.1.30-MariaDB
cURL version: 7.57.0
cURL SSL version: OpenSSL/1.0.2m
WP-Cron url: http://markwebber.org.uk/archive/wp-cron.php
Server self connect: Response Test O.K.
Document root: /home/markwebb/public_html
Temp folder: /home/markwebb/public_html/archive/wp-content/uploads/backwpup-c8fff0-temp/
Log folder: /home/markwebb/public_html/archive/wp-content/uploads/backwpup-e0824-logs/
Server: Apache
Operating System: Linux
PHP SAPI: cgi-fcgi
Current PHP user: markwebb
Maximum execution time: 180 seconds
Alternative WP Cron: Off
Disabled WP Cron: Off
CHMOD Dir: 0755
Server Time: 12:18
Blog Time: 12:18
Blog Timezone: Europe/London
Blog Time offset: 0 hours
Blog language: en-GB
MySQL Client encoding: utf8
PHP Memory limit: 256M
WP memory limit: 40M
WP maximum memory limit: 256M
Memory in use: 14.00 MB
Disabled PHP Functions:: dl, popen, pclose, proc_open, proc_nice, proc_terminate, proc_get_status, proc_close, leak, apache_child_terminate, escape, shellcmd, shell-exec, crack_check, crack_closedict, crack_getlastmessage, crack_opendict, psockopen, php_u, symlink, ini_restore, posix_getpwuid, pfsockopen
Loaded PHP Extensions:: Core, PDO, Phar, Reflection, SPL, SimpleXML, Zend OPcache, bcmath, bz2, calendar, cgi-fcgi, ctype, curl, date, dom, exif, fileinfo, filter, ftp, gd, gettext, hash, iconv, imagick, imap, intl, ionCube Loader, json, libxml, mbstring, mcrypt, mysqli, mysqlnd, openssl, pcntl, pcre, pdo_mysql, pdo_sqlite, posix, pspell, readline, session, soap, sockets, sqlite3, standard, tidy, timezonedb, tokenizer, wddx, xml, xmlreader, xmlrpc, xmlwriter, xsl, zip, zlib

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