function session_start is missing

[cvmiller]

Installed release 3.1.0 in an Alpine 3.15 container.

I have things running for accessing the first page (I assume a login), however HTML screen is just a welcome page (with dimmed outline).

I note the following in the nginx /var/log/nginx/error.log

  thrown in /var/www/localhost/htdocs/lxd-dashboard/backend/config/db.php on line 22" while reading response header from upstream, client: 2607:c000:8011:fd00::32, server: _, request: "GET /backend/config/login.php?action=loadLoginForm HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "[2607:c000:8011:fd00:216:3eff:fe84:8e3e]", referrer: "http://[2607:c000:8011:fd00:216:3eff:fe84:8e3e]/"
2022/01/03 00:07:05 [error] 748#748: *12 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught Error: Call to undefined function session_start() in /var/www/localhost/htdocs/lxd-dashboard/backend/aaa/authentication.php:22
Stack trace:
#0 {main}
  thrown in /var/www/localhost/htdocs/lxd-dashboard/backend/aaa/authentication.php on line 22" while reading response header from upstream, client: 2607:c000:8011:fd00::32, server: _, request: "GET /backend/aaa/authentication.php?action=validateAuthentication HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "[2607:c000:8011:fd00:216:3eff:fe84:8e3e]", referrer: "http://[2607:c000:8011:fd00:216:3eff:fe84:8e3e]/"
2022/01/03 00:07:05 [error] 748#748: *15 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught Error: Call to undefined function session_start() in /var/www/localhost/htdocs/lxd-dashboard/backend/config/db.php:22
Stack trace:
#0 /var/www/localhost/htdocs/lxd-dashboard/backend/config/login.php(31): require_once()
#1 {main}
  thrown in /var/www/localhost/htdocs/lxd-dashboard/backend/config/db.php on line 22" while reading response header from upstream, client: 2607:c000:8011:fd00::32, server: _, request: "GET /backend/config/login.php?action=loadLoginForm HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "[2607:c000:8011:fd00:216:3eff:fe84:8e3e]", referrer: "http://[2607:c000:8011:fd00:216:3eff:fe84:8e3e]/"

Went looking for the function definition in lxd-dashboard/, I see many calls to the function, but no function definition. Perhaps this function is defined elsewhere?

[matthewalanpenning]

Craig, Thanks for posting the error. It looks like Alpine Linux may not have the Session module installed in their default packages. I believe you may have to install the php5-mod-session package. Matt

[cvmiller]

Thanks, installing php7-session, and restarting `php-fpm7' has got past this error. Now I see a registration screen on my web browser.

However, a new error:

 [error] 748#748: *32 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught Error: Class 'PDO' not found in /var/www/localhost/htdocs/lxd-dashboard/backend/config/login.php:133
Stack trace:
#0 {main}
  thrown in /var/www/localhost/htdocs/lxd-dashboard/backend/config/login.php on line 133" while reading response header from upstream, client: 2607:c000:8011:fd00::32, server: _, request: "POST /backend/config/login.php?database_type=sqlite&database_host=&database_name=&database_user=&action=writeDatabaseConfig HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "[2607:c000:8011:fd00:216:3eff:fe84:8e3e]", referrer: "http://[2607:c000:8011:fd00:216:3eff:fe84:8e3e]/"

I am guessing PDO needs to be installed on Alpine, but what is the package name?

[cvmiller]

Found the Alpine package php7-pdo.

However, now when I try to register a user, I get a dialog that pops up (on the web browser) that says "could not find driver" with a checkbox option to not show the error any longer. I don't see anything in the nginx or php error logs.

Any ideas?

[cvmiller]

Found the Alpine package php7-pdo_sqlite

A new errror (in the web dialog)

SQLSTATE[HY000] [14] unable to open database file

And it is true, I don't see a database file in /var/lxdware/data/sqlite Did I miss a step in the installation? How does the sqlite file get created?

[matthewalanpenning]

If you have the php7-pdo-sqlite module installed I would guess that the webserver may not have permissions then to create the database file in /var/lxdware/data/sqlite. I am not sure what user Alpine Linux sets as the user for the webserver. It probably is listed in the /etc/nginx/nginx.conf file on your server. In Debian based systems the default webserver user is www-data. For Alpine, you may have to create a user and configure that user in the nginx.conf file. Then grant write permissions to that user for anything in the /var/lxdware directory.

[cvmiller]

Thanks, for helping me with this. Yes, I do have the php7-pdo_sqlite installed, the default user for nginx under Alpine is nginx. I had already changed the permissions and ownership.

cd /var/lxdware/
/var/lxdware # ls -l
total 0
drwxrwxr-x    1 nginx    www-data         0 Jan  2 23:27 backups
drwxrwxr-x    1 nginx    www-data        18 Jan  2 23:27 data
/var/lxdware # ls -lR 
.:
total 0
drwxrwxr-x    1 nginx    www-data         0 Jan  2 23:27 backups
drwxrwxr-x    1 nginx    www-data        18 Jan  2 23:27 data

./backups:
total 0

./data:
total 0
drwxrwxr-x    1 nginx    www-data         0 Jan  2 23:27 lxd
drwxrwxr-x    1 nginx    www-data         0 Jan  2 23:27 sqlite

./data/lxd:
total 0

./data/sqlite:
total 0

What is the sqlite database file called? Perhaps I can touch it, and make sure the file is writable to user nginx

[matthewalanpenning]

The sqlite database file would be located at /var/lxdware/data/sqlite/lxdware.sqlite and there is a configuration file that should also be created when you first login at /var/lxdware/data/db_config.php. The config file contains the following information within php tags: define( 'DB_TYPE', 'sqlite' ); define( 'DB_NAME', '' ); define( 'DB_USER', '' ); define( 'DB_PASSWORD', '' ); define( 'DB_HOST', '' ); This is created when logging in from https://github.com/lxdware/lxd-dashboard/blob/master/lxd-dashboard/backend/config/login.php lines 130-152.

[cvmiller]

Thanks that is a help. I got it to work by chmod -R o+w to the /var/lxdware directories. So clearly, the user is not nginx or in the group of www-data (since they had write privileges). It could be running as nobody:

PID   USER     TIME  COMMAND
...
 1500 root      0:03 {php-fpm7} php-fpm: master process (/etc/php7/php-fpm.conf)
 1507 nobody    0:00 {php-fpm7} php-fpm: pool www
 1508 nobody    0:00 {php-fpm7} php-fpm: pool www
 1556 root      0:00 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf
 1557 nginx     0:00 nginx: worker process
 1558 nginx     0:00 nginx: worker process
 1559 nginx     0:00 nginx: worker process

Later...

After a bit of work to delete session files and other cruft created by user nobody, and adding the following packages php7-json php7-openssl to Alpine Linux, I can log in.

So far here are the packages that I have had to load (and restart php-fpm7 daemon) to get things going.

apk add nginx php-fpm php-curl sqlite php-sqlite3 php7-session php7-pdo php7-pdo_sqlite php7-json php7-openssl

I also had to change the included nginx file to support the default location and how to talk to PHP (uses a loopback socket) in Alpine Linux:

server {
        listen 80 default_server;
        listen [::]:80 default_server;
        root /var/www/localhost/htdocs/lxd-dashboard;
        index index.php index.html;
        server_name _;

        location / {
                try_files $uri $uri/ =404;
        }

        location ~ \.php$ {
        #include snippets/fastcgi-php.conf;
        #fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
        fastcgi_pass      127.0.0.1:9000;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
        #include snippets/fastcgi-php.conf;
        include fastcgi.conf;
     }
}

And of course change the user in /etc/php7/php-fpm.d/www.conf

 ;user = nobody
 user = nginx  
 ;group = nobody
 group = www-data

Now I can start using the Dashboard, and start enjoying your software! Thanks for all the help.

[matthewalanpenning]

Thanks for sticking with getting the LXD Dashboard on Alpine Linux setup. Your information is very helpful and I will use it to help create a installation guide on the website.