To import a .ovpn file in Gnome Network Manager you just need a simple command to enable the appropriate plugin:
sudo apt-get install network-manager-openvpn-gnome;
.. and as simple as that you can process your .ovpn files from the network manager as you would do with other VPN profiles.
As many people, we came across the following photo:
In this mathematical “proof” the author tries to convince us that there is an error in math and it can be demonstrated using the above example. The steps taken by this person are the following:
a equal to b (a = b).a which results to a^2 = ab.b^2 and we get a^2-b^2 = ab-b^2.(a-b) resulting to (a+b)(a-b) = b(a-b).(a-b) which results to a+b = b.a = b, it replaces a on the left side with a b and produces this state b+b = b => 2b = b.b both sides which results to 2 = 1.The reason that this proof is false is because in step 5, where it divides both sides with (a-b) it really is dividing both sides with 0 (since we know for sure that a = b from step 1) which it cannot be defined as a valid division. So everything from step 5 and forward are invalid and thus the proof is wrong.
Recently, we were trying to update a WordPress installation that was running under apache in a CentOS 7. When we would press the lovely blue button to update WordPress we would get the following error:
The update cannot be installed because we will be unable to copy some files. This is usually due to inconsistent file permissions.: wp-admin/includes/update-core.php
Installation Failed
At first we thought it was an issue with the privileges on the folder, so we did the following steps to fix the issue:
apache server:We executed the following command to get the name of the local user that was handling the apache web server:
ps -ef | grep apache;
From which, we got the following results:
apache 7289 8523 1 10:35 ? 00:00:03 /usr/sbin/httpd -DFOREGROUND
apache 7293 8523 0 10:35 ? 00:00:02 /usr/sbin/httpd -DFOREGROUND
apache 7316 8523 0 10:35 ? 00:00:01 /usr/sbin/httpd -DFOREGROUND
apache 7317 8523 0 10:35 ? 00:00:01 /usr/sbin/httpd -DFOREGROUND
apache 7335 8523 1 10:35 ? 00:00:03 /usr/sbin/httpd -DFOREGROUND
apache 7347 8523 0 10:35 ? 00:00:01 /usr/sbin/httpd -DFOREGROUND
apache 7348 8523 0 10:35 ? 00:00:01 /usr/sbin/httpd -DFOREGROUND
apache 7349 8523 0 10:35 ? 00:00:01 /usr/sbin/httpd -DFOREGROUND
apache 7350 8523 0 10:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 7351 8523 0 10:35 ? 00:00:01 /usr/sbin/httpd -DFOREGROUND
root 8071 7978 0 10:40 pts/1 00:00:00 grep --color=auto apache
The first column is the name of the user, so we found out that apache local user is the user executing the apache web server.
After getting the above information we proceeded to update the access rights in our WordPress installation folder (/var/www/example.com)
find /var/www/example.com -type d -exec chmod 755 '{}' \;
find /var/www/example.com -type f -exec chmod 644 '{}' \;
chown -R apache:apache /var/www/example.com;
To our disappointment, nothing changed and we would still get the same error. Luckily enough we had another ace in our sleeve!
We executed the following command (ls -Z) to get the security context of the files and folders in the installation folder of WordPress:
ls -Z /var/www/example.com;
Where we got the following results:
drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 api -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 favicon.ico -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 index.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 license.txt -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 readme.html -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 r-file.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wordfence-waf.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-activate.php drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-admin -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-blog-header.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-comments-post.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-config.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-config-sample.php drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_rw_content_t:s0 wp-content -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-cron.php drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-includes -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-links-opml.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-load.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-login.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-mail.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-settings.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-signup.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 wp-trackback.php -rw-r--r--. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 xmlrpc.php
What we got from this result: all files and folders marked with the httpd_sys_content_t are not directly editable by the apache web server even though the user has the rights to do so as it is a security step by SELinux.
httpd_sys_content_t
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/managing_confined_services/sect-managing_confined_services-the_apache_http_server-types
Use this type for static web content, such as.htmlfiles used by a static website. Files labeled with this type are accessible (read only) tohttpdand scripts executed byhttpd. By default, files and directories labeled with this type cannot be written to or modified byhttpdor other processes. Note that by default, files created in or copied into/var/www/html/are labeled with thehttpd_sys_content_ttype.
We just changed the security context for the folders and files to httpd_sys_rw_content_t which allows apache web server to edit the files:
httpd_sys_rw_content_t
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/managing_confined_services/sect-managing_confined_services-the_apache_http_server-types
Files labeled with this type can be written to by scripts labeled with thehttpd_sys_script_exec_ttype, but cannot be modified by scripts labeled with any other type. You must use thehttpd_sys_rw_content_ttype to label files that will be read from and written to by scripts labeled with thehttpd_sys_script_exec_ttype.
chcon -R --type httpd_sys_rw_content_t /var/www/example.com;
After this command finished, we updated WordPress as normal!
(In case you want to change the security context back to the original just execute chcon with httpd_sys_content_t as parameter on the folders and files you want to operate as read-only).
Most cars (if not all) consume energy even when they are parked, with the engine off and no visible systems working. Electrical systems including the clock and on-board computer systems drain the battery little by little until they completely empty it.
When the energy level in a battery is low, it might prevent it from being capable to start your car and you will need a boost to get your car running again. In worse scenarios, batteries that are completely drained can get damaged and they need to be replaced.
Therefore, if you do not move your car for a long period (like during the lock-down period), then the extended lack of use might damage the battery and cause it to need replacement.
Check the operation manual of your car or contact your dealer prior to disconnecting the battery. (We are not sure if there is a car out there that would not like having its battery removed)
Disconnect the battery from you car to stop the energy draining.
To do so remove the cable from the negative port (has the minus sign "-" and is usually black colored).
Do not let the negative and positive cable exposed metal ends touch under any circumstances.
