My clamscan is taking a lot of CPU & memory of my vps. I use Virtualmin as the control panel. How can I disable Clamscan and Spamassign from taking excessive cpu and memory?
Solution
If you are receiving an inbound spam attack or an email bounce attack on your VPS, and you use Clamscan and Spamassasign for your incoming mail filtering, it is highly possible that, you will run out of RAM and CPU. To solve the problem, you need to disable Clamscan and Spamassign for at least the time you are dealing with the attack or have developed a way to deal the attack. To disable Clamd and Spamassasign, you may follow the following steps
How to Disable Clamd and Spamassasign
First login to your virtualmin 10000 port, and go to System Settings >> Features and Plugins
Now uncheck the options ‘Spam filtering’ and ‘Virus filtering’ option and save it
Now go to your Webmin tab >> Under the System >> Bootup and Shutdown
Now select the services with the name ‘clam’ and ‘spamassassin.service’, then click on ‘Disable now and on boot’ option. Once saved, also make sure they are saying ‘No’ in running. If not, select them again and go to the bottom of the page, and press ‘Stop’ to shut them down immediately.
If you are using virtualmin as a control panel, you use 10000 port to login to your control panel. It shall look like the following:
https://your.hostname.com:10000
Now, if your browser says something like the following:
It means your webmin is either down or crashed.
Restart Virtualmin or Restart Webmin
To solve this, you may start the webmin by logging to your SSH and running the following command:
service webmin start
or
/etc/init.d/webmin start
In case, you need to double sure to stop the service, you may do the following:
service webmin stop
or
/etc/init.d/webmin stop
Once you done, stopping, make sure to start it with the following:
service webmin start
or
/etc/init.d/webmin start
Once the webmin starts successfully, you may access your virtulmin control panel on port 10000, either with your hostname or the IP, like the following:
https://your.hostname.com:10000
or
https://11.11.11.11:10000
(replace 11.11.11.11 with your server IP)
I want to change the memory_limit of a virtual host in virtualmin. How can I do that?
Solution
First, login to Virtualmin on port 10000, now, select the virtual host from the dropdown under Virtualmin tab. Now under the services, there are PHP 5 Configuration and PHP 7 Configuration
Click on the version you want to change configuration for. It will show you a list of options to change php variables.
Now there is ‘Resource Limit’, that contains the options like maximum execution time, or memory limit for PHP.
Now, change the ‘Maximum Memory Allocation’ option to something that you want to change memory_limit of php in virtualmin
After you have completed updating your yum, you saw the kernel got updated, and hence restarted the server to take the new kernel. But you find out that the server has never come online. Once you visit the KVM or Serial Console (SOL) of the system, you could see, your system is booted to ‘grub>’ console instead of booting from disk. How can you fix the system now?
Solution Intro
This specific issue can appear for any linux server, along with many reasons. Although, if you are running an server from OVH and had faced a similar issue, the boat I am going to show you can navigate to destination. Please note, in many other case of similar situation, you might end up fixing the grub with the same solution.
What and How the Problem Happened
OVH has an interesting strategy of booting. They follow everything through network PXE, even if it is not ‘netboot’, but just the local drives. For this to work out, you need PXE to take the latest grub details pushed once a kernel is updated. This is one reason why, OVH also supplies a custom kernel from a cusstom repo. Although, if you are using the stock kernel, you might come up with a situation, where the latest grub hasn’t been pushed to PXE and your system fails to boot from drives. It then puts you in the ‘grub’ of network.
How to Fix the Problem
Now, one thing is clear, after you completed a kernel update, your grub is broken due to the latest machine code is not available to the booting system. You can go and follow a regular grub repair method for Grub 2, to fix the situation. A couple of things to remember, as your system’s grub is failing to load, you have to use an independent rescue kernel to fix this, this could either be from a personal network repository or a rescue disk available from your datacenter’s location, like ovh has one. Another thing to remember, is that, if you are using CentOS 7 or Ubuntu with UEFI system, using mdadm or linux software raid, it is highly likely, your boot efi is placed in a non raid partition. Preferably in the first drive’s first partition. You can always verify this from your fstab file.
So the first job, is to boot your system into the rescue disk/cd/kernel. I assume you have done that with no difficulty. Once done, first mount your partitions. In OVH cases, it loads the mdadm automatically. In my case, it was /dev/md2.
mount /dev/md2 /mnt
# check what partition is used for /boot/efi
nano /mnt/etc/fstab
# in my case, it is /dev/nvme0n1p1 (It is a NVMe SSD, and the first partion is used for efi storage
mount /dev/nvme0n1p1 /mnt/boot/efi
Once we have mounted the partitions successfully, you may now chroot the system. Before chrooting, you want the dev, proc and sys to use the /mnt partitions respectively:
mount --bind /dev /mnt/dev
mount --bind /proc /mnt/proc
mount --bind /sys /mnt/sys
If these all goes well, now we can chroot the system:
chroot /mnt
Now you have successfully changed the root directory of the rescue kernel to the original drive’s root. All you need to do, is to remake the grub config, that will immediately generate the grub.cfg file and sync the machine code:
# we know grub.cfg is available in /boot/grub2/grub.cfg
grub2-mkconfig -o /boot/grub2/grub.cfg
# once this is finished, we have to make sure, grub is also installed for both disks, for my case, these are /dev/nvme0n1 and /dev/nvme1n1
grub2-install /dev/nvme0n1
grub2-install /dev/nvme1n1
If you see the response is ‘No Error Reported’, then you are good go. You may now reboot your system back to hard disk, and can see your grub is able to load the latest kernel you installed from the original hard disk. Remember, for safety, you should umount all the partition, to avoid any data loss due to OS page cache:
When we try to run a composer command, like update, we usually do the following:
composer update
Cpanel has multiple PHP binaries, but in this case, we are unable to select a specific PHP binary to use, instead we have to run it with the default one, how to run composer update with a different php binary in cpanel?
Solution
composer binary file, is a phar file. PHAR is necessarily a PHP Archive and usually automatically detect the running php. But as it is essentially written in php, you may explicitly run it with a different php binary, if you want. To run composer with different php binary, first, you need to find the location of composer. You may do so, using the following:
root@mirage [~]# which composer
/opt/cpanel/composer/bin/composer
Cpanel different php binaries are available under the following kind of directory:
/opt/cpanel/ea-phpXX/usr/bin/php
XX is the version number of PHP. So for example if you need to use PHP 7.4, you would need to run using the following:
/opt/cpanel/ea-php74/usr/bin/php
Now, to run composer update along with PHP 7.4 binary, you may do something like the following:
First, make sure you are in the directory where you want to install laravel, for example, something like the following:
cd /home/username/public_html
Then, you may run the above command:
/opt/cpanel/ea-php74/usr/bin/php /opt/cpanel/composer/bin/composer update
or in case, you want to to install
/opt/cpanel/ea-php74/usr/bin/php /opt/cpanel/composer/bin/composer install
or may be, you wan to run update with no-scripts
/opt/cpanel/ea-php74/usr/bin/php /opt/cpanel/composer/bin/composer update --no-scripts
While trying to run any of the following with Laravel composer installer, you see an error similar to the following:
Uncaught ErrorException: require(/home/username/public_html/vendor/composer/../../app/Helpers/helper.php): failed to open stream: No such file or directory in /home/username/public_html/vendor/composer/autoload_real.php:71
How to fix this?
Solution
The error is appearing, most likely you forgot to add the ‘app’ directory of laravel in your root directory. Make sure, you have the ‘app’ directory in your root directory, then run any of the following:
If this is the first time, you need all laravel packages, run:
composer install
If this is not the first time, you may run the following:
It is trying to look into a sub-sub version of openssl, which is 1h for PHP 7.4, but 1i is installed by default which is not an exact match with 1h, hence the error is appearing. To fix the problem, you can not just run yum update on openssl and fix this as you technically already have the latest version. To work with this, you need to first uninstall the ea-openssl rpm and install the require version. You may do this in the following way:
[root@stack4 yum.repos.d]# rpm -qa|grep ea-openssl
ea-openssl11-devel-1.1.1i-1.el7.cloudlinux.x86_64
ea-openssl-1.0.2u-1.el7.cloudlinux.x86_64
ea-openssl11-1.1.1i-1.el7.cloudlinux.x86_64
[root@stack4 yum.repos.d]# yum install ea-openssl11-1.1.1h-1.el7.cloudlinux.x86_64
Loaded plugins: fastestmirror, rhnplugin, universal-hooks
This system is receiving updates from CLN.
Loading mirror speeds from cached hostfile
* cpanel-plugins: 185.125.185.32
* cloudlinux-x86_64-server-7: xmlrpc.cln.cloudlinux.com
Package matching 1:ea-openssl11-1.1.1h-1.el7.cloudlinux.x86_64 already installed. Checking for update.
Nothing to do
Remember to use rpm uninstaller instead of yum remove, as yum also removes the dependencies, but with rpm you can skip the dependency uninstallation and patch it the above way.
When run the following command in your Laravel Automation Tool Dusk:
php artisan dusk
You get something like the following error:
[elastic-keldysh@pl1 blog]$ php artisan dusk
PHPUnit 9.3.11 by Sebastian Bergmann and contributors.
E 1 / 1 (100%)
Time: 00:00.339, Memory: 18.00 MB
There was 1 error:
1) Tests\Browser\ExampleTest::testBasicExample
Facebook\WebDriver\Exception\UnknownErrorException: unknown error: cannot find Chrome binary
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/php-webdriver/webdriver/lib/Exception/WebDriverException.php:139
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/php-webdriver/webdriver/lib/Remote/HttpCommandExecutor.php:370
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/php-webdriver/webdriver/lib/Remote/RemoteWebDriver.php:136
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/tests/DuskTestCase.php:40
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:200
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/framework/src/Illuminate/Support/helpers.php:234
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:201
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:95
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:65
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/tests/Browser/ExampleTest.php:21
ERRORS!
Tests: 1, Assertions: 0, Errors: 1.
The error actually appears because you do not have Chrome browser installed on your system. Now, exit from your user shell, and drop back to the root shell. From the root shell, if you are using CentOS 7, you may run the following:
Once the installation is done, you may now go back to the user shell and run laravel dusk:
[root@pl1 lib64]# su - elastic-keldysh
Last login: Thu Oct 1 15:39:18 IST 2020 on pts/0
[elastic-keldysh@pl1 ~]$ php artisan dusk
Could not open input file: artisan
[elastic-keldysh@pl1 ~]$ cd blog
[elastic-keldysh@pl1 blog]$ php artisan dusk
PHPUnit 9.3.11 by Sebastian Bergmann and contributors.
R 1 / 1 (100%)
Time: 00:02.367, Memory: 18.00 MB
There was 1 risky test:
1) Tests\Browser\ExampleTest::testBasicExample
This test did not perform any assertions
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/tests/Browser/ExampleTest.php:16
OK, but incomplete, skipped, or risky tests!
Tests: 1, Assertions: 0, Risky: 1.
If you are looking at this post, chances high that, you are trying to run laravel dusk and seeing the following kind of error:
[elastic-keldysh@pl1 blog]$ php artisan dusk
PHPUnit 9.3.11 by Sebastian Bergmann and contributors.
E 1 / 1 (100%)
Time: 00:00.331, Memory: 18.00 MB
There was 1 error:
1) Tests\Browser\ExampleTest::testBasicExample
Facebook\WebDriver\Exception\WebDriverCurlException: Curl error thrown for http POST to /session with params: {"capabilities":{"firstMatch":[{"browserName":"chrome","goog:chromeOptions":{"binary":"","args":["--disable-gpu","--headless"]}}]},"desiredCapabilities":{"browserName":"chrome","platform":"ANY","chromeOptions":{"binary":"","args":["--disable-gpu","--headless"]}}}
Failed to connect to localhost port 9515: Connection refused
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/php-webdriver/webdriver/lib/Remote/HttpCommandExecutor.php:331
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/php-webdriver/webdriver/lib/Remote/RemoteWebDriver.php:136
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/tests/DuskTestCase.php:40
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:200
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/framework/src/Illuminate/Support/helpers.php:234
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:201
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:95
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/vendor/laravel/dusk/src/Concerns/ProvidesBrowser.php:65
/var/www/vhosts/elastic-keldysh.139-99-24-82.plesk.page/blog/tests/Browser/ExampleTest.php:21
ERRORS!
Tests: 1, Assertions: 0, Errors: 1.
Chorme/Chromium browser runs it’s on 9515 port and laravel dusk tries to connect to it through the Browser binary, but failing to do so. To resolve the case, we first, need to check if chromedriver for linux can run or not.
First, browse your laravel root directory, in my case, it’s the blog directory and then run the chromedriver for linux as following:
cd blog
vendor/laravel/dusk/bin/chromedriver-linux
This should return something like the following if the driver able to load in memory:
[elastic-keldysh@pl1 blog]$ vendor/laravel/dusk/bin/chromedriver-linux Starting ChromeDriver 85.0.4183.87 (cd6713ebf92fa1cacc0f1a598df280093af0c5d7-refs/branch-heads/4183@{#1689}) on port 9515 Only local connections are allowed. Please see https://chromedriver.chromium.org/security-considerations for suggestions on keeping ChromeDriver safe. ChromeDriver was started successfully.
But if it can not be loaded, it will return some kind of error like the following:
[elastic-keldysh@pl1 blog]$ vendor/laravel/dusk/bin/chromedriver-linux
vendor/laravel/dusk/bin/chromedriver-linux: error while loading shared libraries: libX11-xcb.so.1: cannot open shared object file: No such file or directory
As the error suggests, it is failing to access the library called libX11-xcb. To install it in CentOS, you may run the following from root shell:
You may now, go back to the user shell, and run the chromedriver-linux again:
[root@pl1 lib64]# su - elastic-keldysh
Last login: Thu Oct 1 15:28:29 IST 2020 on pts/0
[elastic-keldysh@pl1 ~]$ cd blog
[elastic-keldysh@pl1 blog]$ vendor/laravel/dusk/bin/chromedriver-linux
Starting ChromeDriver 85.0.4183.87 (cd6713ebf92fa1cacc0f1a598df280093af0c5d7-refs/branch-heads/4183@{#1689}) on port 9515
Only local connections are allowed.
Please see https://chromedriver.chromium.org/security-considerations for suggestions on keeping ChromeDriver safe.
ChromeDriver was started successfully.
Now, you may run the following to start using the laravel dusk:
php artisan dusk
After you are done resolving the 9515 error, you might also have to face another error with Chrome Binary, have a look at the following on how to resolve the error:
