Upgrade to 18.01 and PHP 7.3 has broken installation

I have just upgraded to NC 18.01 and had to do a PHP upgrade from 7.1 to 7.3 on my Centos 7 server as a prerequisite. Both upgrades appeared to go well however now I can’t login to my NC with the following displayed when I enter the URL:

"Internal Server Error

The server encountered an internal error and was unable to complete your request.
Please contact the server administrator if this error reappears multiple times, please include the technical details below in your report.
More details can be found in the server log."

I have restarted the Apache service, rebooted the server and re-installed PHP 7.3 with no effect. I also restored my NC 17 backup but it still errors. Concurrently I also run 2 websites on the server and they’re working ok, it’s just the NC instance that’s failing. Reading the log I believe my problem might be related to the PHP upgrade breaking something connecting to NC but I’m only new to this so I was wondering if anyone could shed some light on what might be causing the problem and how I might fix it?

The entries written to the log each time I try and access the URL are:

“{“reqId”:“XlG2w0yB3zypNSP9kp@hpQAAAAA”,“level”:3,“time”:“2020-02-22T23:18:27+00:00”,“remoteAddr”:“124.182.33.48”,“user”:”–",“app”:“index”,“method”:“GET”,“url”:"/xxxxxxx/",“message”:{“Exception”:“OC\HintException”,“Message”:“Memcache \OC\Memcache\APCu not available for local cache”,“Code”:0,“Trace”:[{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:512,“function”:"__construct",“class”:“OC\Memcache\Factory”,“type”:"->",“args”:[“8a63f8caad8fae9a443234c0cdd3c67f”,{“class”:“OC\Log”},"\OC\Memcache\APCu","\OC\Memcache\APCu",null]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:118,“function”:“OC\{closure}”,“class”:“OC\Server”,“type”:"->",“args”:["*** sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“OC\Memcache\Factory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/AppFramework/Utility/SimpleContainer.php",“line”:161,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“OC\Memcache\Factory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:114,“function”:“OC\AppFramework\Utility\{closure}”,“class”:“OC\AppFramework\Utility\SimpleContainer”,“type”:"->",“args”:[" sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“MemCacheFactory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:1535,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“MemCacheFactory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:691,“function”:“getMemCacheFactory”,“class”:“OC\Server”,“type”:"->",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:118,“function”:“OC\{closure}”,“class”:“OC\Server”,“type”:"->",“args”:[" sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“OC\App\AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/AppFramework/Utility/SimpleContainer.php",“line”:161,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“OC\App\AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:114,“function”:“OC\AppFramework\Utility\{closure}”,“class”:“OC\AppFramework\Utility\SimpleContainer”,“type”:"->",“args”:[" sensitive parameters replaced ***"]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:1725,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/legacy/app.php",“line”:346,“function”:“getAppManager”,“class”:“OC\Server”,“type”:"->",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/legacy/app.php",“line”:114,“function”:“getEnabledApps”,“class”:“OC_App”,“type”:"::",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/base.php",“line”:640,“function”:“loadApps”,“class”:“OC_App”,“type”:"::",“args”:[[“session”]]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/base.php",“line”:1078,“function”:“init”,“class”:“OC”,“type”:"::",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/index.php",“line”:40,“args”:["/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/base.php"],“function”:“require_once”}],“File”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Memcache/Factory.php",“Line”:99,“Hint”:“Is the matching PHP module installed and enabled?”,“CustomMessage”:"–"},“userAgent”:“Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:73.0) Gecko/20100101 Firefox/73.0”,“version”:“17.0.2.1”}

{“reqId”:“XlG2w0yB3zypNSP9kp@hpQAAAAA”,“level”:3,“time”:“2020-02-22T23:18:27+00:00”,“remoteAddr”:“124.182.33.48”,“user”:"–",“app”:“index”,“method”:“GET”,“url”:"/xxxxxxx/",“message”:{“Exception”:“OC\HintException”,“Message”:“Memcache \OC\Memcache\APCu not available for local cache”,“Code”:0,“Trace”:[{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:512,“function”:"__construct",“class”:“OC\Memcache\Factory”,“type”:"->",“args”:[“8a63f8caad8fae9a443234c0cdd3c67f”,{“class”:“OC\Log”},"\OC\Memcache\APCu","\OC\Memcache\APCu",null]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:118,“function”:“OC\{closure}”,“class”:“OC\Server”,“type”:"->",“args”:["*** sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“OC\Memcache\Factory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/AppFramework/Utility/SimpleContainer.php",“line”:161,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“OC\Memcache\Factory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:114,“function”:“OC\AppFramework\Utility\{closure}”,“class”:“OC\AppFramework\Utility\SimpleContainer”,“type”:"->",“args”:[" sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“MemCacheFactory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:1535,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“MemCacheFactory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:691,“function”:“getMemCacheFactory”,“class”:“OC\Server”,“type”:"->",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:118,“function”:“OC\{closure}”,“class”:“OC\Server”,“type”:"->",“args”:[" sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“OC\App\AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/AppFramework/Utility/SimpleContainer.php",“line”:161,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“OC\App\AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:114,“function”:“OC\AppFramework\Utility\{closure}”,“class”:“OC\AppFramework\Utility\SimpleContainer”,“type”:"->",“args”:[" sensitive parameters replaced ***"]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:1725,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/legacy/template.php",“line”:284,“function”:“getAppManager”,“class”:“OC\Server”,“type”:"->",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/index.php",“line”:51,“function”:“printErrorPage”,“class”:“OC_Template”,“type”:"::",“args”:[“Memcache \OC\Memcache\APCu not available for local cache”,“Is the matching PHP module installed and enabled?”,503]}],“File”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Memcache/Factory.php",“Line”:99,“Hint”:“Is the matching PHP module installed and enabled?”,“CustomMessage”:"–"},“userAgent”:“Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:73.0) Gecko/20100101 Firefox/73.0”,“version”:“17.0.2.1”}

{“reqId”:“XlG2w0yB3zypNSP9kp@hpQAAAAA”,“level”:3,“time”:“2020-02-22T23:18:27+00:00”,“remoteAddr”:“124.182.33.48”,“user”:"–",“app”:“core”,“method”:“GET”,“url”:"/xxxxxxx/",“message”:{“Exception”:“OC\HintException”,“Message”:“Memcache \OC\Memcache\APCu not available for local cache”,“Code”:0,“Trace”:[{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:512,“function”:"__construct",“class”:“OC\Memcache\Factory”,“type”:"->",“args”:[“8a63f8caad8fae9a443234c0cdd3c67f”,{“class”:“OC\Log”},"\OC\Memcache\APCu","\OC\Memcache\APCu",null]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:118,“function”:“OC\{closure}”,“class”:“OC\Server”,“type”:"->",“args”:["*** sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“OC\Memcache\Factory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/AppFramework/Utility/SimpleContainer.php",“line”:161,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“OC\Memcache\Factory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:114,“function”:“OC\AppFramework\Utility\{closure}”,“class”:“OC\AppFramework\Utility\SimpleContainer”,“type”:"->",“args”:[" sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“MemCacheFactory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:1535,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“MemCacheFactory”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:691,“function”:“getMemCacheFactory”,“class”:“OC\Server”,“type”:"->",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:118,“function”:“OC\{closure}”,“class”:“OC\Server”,“type”:"->",“args”:[" sensitive parameters replaced "]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“OC\App\AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/AppFramework/Utility/SimpleContainer.php",“line”:161,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“OC\App\AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/3rdparty/pimple/pimple/src/Pimple/Container.php",“line”:114,“function”:“OC\AppFramework\Utility\{closure}”,“class”:“OC\AppFramework\Utility\SimpleContainer”,“type”:"->",“args”:[" sensitive parameters replaced ***"]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/ServerContainer.php",“line”:120,“function”:“offsetGet”,“class”:“Pimple\Container”,“type”:"->",“args”:[“AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Server.php",“line”:1725,“function”:“query”,“class”:“OC\ServerContainer”,“type”:"->",“args”:[“AppManager”]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/legacy/app.php",“line”:346,“function”:“getAppManager”,“class”:“OC\Server”,“type”:"->",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/legacy/app.php",“line”:114,“function”:“getEnabledApps”,“class”:“OC_App”,“type”:"::",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/base.php",“line”:640,“function”:“loadApps”,“class”:“OC_App”,“type”:"::",“args”:[[“session”]]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/base.php",“line”:1078,“function”:“init”,“class”:“OC”,“type”:"::",“args”:[]},{“file”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/index.php",“line”:40,“args”:["/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/base.php"],“function”:“require_once”}],“File”:"/home/xxxxxxxxxxxxxxx/public_html/xxxxxxx/lib/private/Memcache/Factory.php",“Line”:99,“Hint”:“Is the matching PHP module installed and enabled?”,“CustomMessage”:"–"},“userAgent”:“Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:73.0) Gecko/20100101 Firefox/73.0”,“version”:“17.0.2.1”}

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the matching PHP module installed and enabled?”,“CustomMessage”:"–"},“userAgent”:“Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:73.0) Gecko/20100101 Firefox/73.0”,“version”:“17.0.2.1”}

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Hi smokey

I had a common issue when upgrading from NC 14 to 17. where I also had to update php7.0 to php 7.2.
Though I have a different OS Check the php modules

php -m
php7.3 -m

and see if all needed are there.

php7.3-cli php7.3-common php7.3-mbstring php7.3-gd php-imagick php7.3-intl php7.3-bz2 php7.3-xml php7.3-mysql php7.3-zip php7.3-dev php7.3-curl php7.3-fpm php-dompdf php-apcu redis-server php-redis php-smbclient php7.3-ldap

Hope this helps in any way.

In addition to the PHP modules listed by @Vincent_Stans, your log messages suggest you also need the PHP extension apcu. (I assume your Nextcloud configuration includes memcache.local => '\\OC\\Memcache\\APCu'. My config uses double backslashes, but I believe single backslashes are equivalent.)

On my Ubuntu 16.04 server running Nextcloud 17.0.3, the PHP extension apcu is provided by the apt package php-apcu. The extension is loaded by the line extension=apcu.so in /etc/php/7.3/apache2/conf.d/20-apcu.ini.

(I have not yet followed the advice in the Nextcloud doc to explicitly enable apcu in the PHP CLI (command line interpreter) configuration, but I haven’t seen any ill effects. My /etc/php/7.3/cli/conf.d/20-apcu.ini does load the extension, but the default PHP configuration enables apcu only in Apache, not CLI.)

Unrelated: Your log also includes a warning message that recommends installing the PHP extension intl. On my server, that’s provided by the package php-intl.

Sorry for my late reply and thanks so much to the 2 posters - both of the responses had information that helped me resolve the issue. Basically my problem was caused by having PHP modules installed from different sources and the upgrade didn’t handle that. There might have been a better way to resolve it but my solution was to completely remove all installed versions of PHP and only reinstall the current version from a single source from scratch.