Check your PHP FPM conf in Apache if you have trouble updating Backdrop.
Yesterday I found a solution to Backdrop CMS update problem I'd had for some time. Updating via web interface would fail due to following error:
- Error installing / updating - File transfer failed, reason //var/www/example.com/modules/[module name] is outside of the /var/www/example.com
After asking about the error in the Backdrop CMS forum and receiving a few unhelpful answers I turned my eye to the Apache and PHP FPM settings instead. The double dash in front of the module path suggested a configuration error but all the other PHP-based sites & services (including Drupal 7) I was running were working just fine.
As these things usually go, this was only small syntax error in apache2.conf file. I had this below directory options:
# use FCGI instead of apache's own <FilesMatch \.php$> # default to newest: PHP 7.3 SetHandler "proxy:unix:/run/php/php7.3-fpm.sock|fcgi://localhost/" </FilesMatch>
Could that trailing slash after localhost be the source of problem? So I tried the following:
# use FCGI instead of apache's own <FilesMatch \.php$> # default to newest: PHP 7.3 # NO TRAILING SLASH AFTER LOCALHOST SetHandler "proxy:unix:/run/php/php7.3-fpm.sock|fcgi://localhost" </FilesMatch>
And guess what? Backdrop updates correctly!