MySQL correct permissions
If somehow someone messes up the MySQL folder permissions and you need the MySQL correct permissions, they can be found below:
chmod -v 0751 /var/lib/mysql chown -R mysql:mysql /var/lib/mysql
InnoDB: Ignoring tablespace for because it could not be opened.
This one was a little tricky. The same system where the junior admin made a little mess of the MariaDB server, there was this long string of errors about “InnoDB: Ignoring tablespace for because it could not be opened.” Apparently, somehow the db got deleted manually from the filesystem and we got left with a zillion of these:
2023-08-22 19:04:31 0 [Warning] InnoDB: Ignoring tablespace for `foo`.`core_layout_link` because it could not be opened.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
2023-08-22 19:04:31 0 [ERROR] InnoDB: The error means the system cannot find the path specified.
2023-08-22 19:04:31 0 [ERROR] InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Cannot open datafile for read-only: ‘./foo/core_layout_update.ibd’ OS error: 71
2023-08-22 19:04:31 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
2023-08-22 19:04:31 0 [ERROR] InnoDB: The error means the system cannot find the path specified.
2023-08-22 19:04:31 0 [ERROR] InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Could not find a valid tablespace file for “foo`.`core_layout_update“. Please refer to https://mariadb.com/kb/en/innodb-data-dictionary-troubleshooting/ for how to resolve the issue.
2023-08-22 19:04:31 0 [Warning] InnoDB: Ignoring tablespace for `foo`.`core_layout_update` because it could not be opened.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
2023-08-22 19:04:31 0 [ERROR] InnoDB: The error means the system cannot find the path specified.
2023-08-22 19:04:31 0 [ERROR] InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Cannot open datafile for read-only: ‘./foo/core_resource.ibd’ OS error: 71
2023-08-22 19:04:31 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
2023-08-22 19:04:31 0 [ERROR] InnoDB: The error means the system cannot find the path specified.
2023-08-22 19:04:31 0 [ERROR] InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Could not find a valid tablespace file for “foo`.`core_resource“. Please refer to https://mariadb.com/kb/en/innodb-data-dictionary-troubleshooting/ for how to resolve the issue.
2023-08-22 19:04:31 0 [Warning] InnoDB: Ignoring tablespace for `foo`.`core_resource` because it could not be opened.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
2023-08-22 19:04:31 0 [ERROR] InnoDB: The error means the system cannot find the path specified.
2023-08-22 19:04:31 0 [ERROR] InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Cannot open datafile for read-only: ‘./foo/paypal_ipn_log.ibd’ OS error: 71
2023-08-22 19:04:31 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
2023-08-22 19:04:31 0 [ERROR] InnoDB: The error means the system cannot find the path specified.
2023-08-22 19:04:31 0 [ERROR] InnoDB: If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
2023-08-22 19:04:31 0 [ERROR] InnoDB: Could not find a valid tablespace file for “foo`.`paypal_ipn_log“. Please refer to https://mariadb.com/kb/en/innodb-data-dictionary-troubleshooting/ for how to resolve the issue.
Now, “foo” being the db name, apparently i need to recreate the file structure in /var/lib/mysql and then i can go ahead and restart the sql server and delete the db and everything should go back to normal.
Because they were too many of these, i had to do a little bash wizardry to automate the process and make it a little faster:
cat mysql.err |grep “Could not find a valid tablespace file” |cut -d ‘`’ -f 5 >> list
This would get me a list of the tables, while using ‘`’ as the delimiter for the field i was trying to find. i just cycled between the fields numbers before i got to the right one
So we go to the MySQL folder and re-create the foo db folder (where foo is the db name):
cd /var/lib/mysql
mkdir foo
Then i made this script, that would create the required files:
cd foo
nano x.sh
#!/bin/bash -x
list=$(cat ./list)# Loopty loop
for item in $list; do
touch $item.frm
touch $item.ibd
done
chmod 700 x.sh
./x.sh
Now we have to adjust permissions on the db folder and the files inside:
cd /var/lib/mysql
chown -R mysql:mysql foo
restart mysql and go ahead and delete the foo db and the errors should be gone.
Cheers!
Can’t lock aria control file ‘/var/lib/mysql/aria_log_control
Apparently somehow they managed to start 2 instances of MariaDB that ran concurrently and they were each locking the files for another and this error kept popping in the log: “Can’t lock aria control file ‘/var/lib/mysql/aria_log_control”
Very surprised to see this one, but appeared on a server where a junior admin made a mess of a database, so i was called in to help.
In order to fix, i had to stop the monitoring scripts, and the automatic SQL restart, then i checked for all MySQL running processes, killed them, and started the db properly, while verifying in the logs to see if anything got broken due to the abrupt interruption.
A good practice after this is to run a repair on all databases, to make sure everything is in order
nmcli set nameservers (fix resolv.conf override)
If your /etc/resolv.conf gets overridden by NetworkManager on reboot, then you need to use nmcli to set nameservers in the way below:
1 – find the connection you want to edit
nmcli connection show
2 – add the nameservers
nmcli c modify “connection name” +ipv4.dns “8.8.8.8 9.9.9.9”
3 – reboot
Enjoy
curl: (60) SSL certificate problem: certificate has expired
if you’re trying to debug a website and you’re running some curl request and this might be a staging website or otherwise, with a self-signed ssl certificate maybe, then you could be running into: curl: (60) SSL certificate problem: certificate has expired
A real quick fix is to set curl to accept insecure connections by default in this manner:
echo “insecure” >> ~/.curlrc
Curl away!