Ken's Tech Note

In the recent version of Ubuntu with MySQL / MariaDB, phpMyAdmin can no longer be used via "root". This is because MySQL is now default to use UNIX auth_socket plugin for login for "root". The solution is to set the root user to use mysql_native_password plugin again. $ sudo mysql - u root mysql > USE mysql ; mysql > UPDATE user SET plugin = 'mysql_native_password' WHERE User = 'root' ; mysql > FLUSH PRIVILEGES ; mysql > exit ; $ service mysql restart

Technically, NginX is not vulnerable to Slowloris attack. But the default configurations may not be able to handle Slowloris attack. HEXADIX has published a how-to that is simple to follow: https://hexadix.com/slowloris-dos-attack-mitigation-nginx-web-server/ The key steps are to increase the value of certain variables: Under nginx.conf, add the followings: worker_rlimit_nofile 102400; events { worker_connections 100000; } Check the system and user open file limit.

After standard installation of Perfect Server Ubuntu 16.04LTS, the LetsEncrypt fails to activate. The error log has the following errors: Deserialization error: Wrong directory fields Try re-install Lets Encrypt https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-16-04 sudo add-apt-repository ppa:certbot/certbot sudo apt-get update sudo apt-get install python-certbot-nginx Then return to ISPConfig panel and try to activate again.

Problem: Restoring a wordpress site using BackupBuddy on ISPConfig / nginx. The home page looks fine, but other pages becomes Error 404. Solution: Edit the nginx conf.d/sites-available/yoursite.vhost Add this at the end of the file, just before the final }.        if (!-e $request_filename) { rewrite ^.*$ /index.php last; }if (!-e $request_filename) { rewrite ^.*$ /index.php last; } Another official change is documented at WordPress.org standard. Source: https://codex.wordpress.org/Nginx Add this, or create the new location / block location / { # This is cool because no php is touched for static content. # include the "?$args" part so non-default permalinks doesn't break when using query string try_files $uri $uri/ /index.php?$args; }

To follow the previous blog article, what if we need to extend /var by moving it to another partition? The following article outlines the key steps. Meanwhile, I found some of the steps are only required if you have SELINUX enabled. The key steps are: 1) Launch a new EBS, choose SSD for speed, or HDD for higher volume. 2) Attach the EBS to the server instance. 3) Login via SSH client. 4) fdisk /dev/xvdf - Note when you provision a new EBS and attach it to EC2, it will say it will rename automatically to /dev/xvdf through /xvdp 5 )mkfs -t ext4 /dev/xvdf1 - format new partition for Linux use 6) mount /dev/xvdf1 /mnt - mount it at /mnt 7) shopt -s dotglob - copy files from /var to /mnt rsync -aulvXpogtr /var/* /mnt 8) umount /mnt - unmount 9) Edit /etc/fstab /dev/xvdf1   /var       ext4    defaults,noatime,nofail 0   2 10) mv /var/ /var.old - change the original to become a backup 11) mkdir /var - re-create the /v...

The EC2 standard EBS is 8G. Planning a simple single EBS instance, the EBS will also contain / and root partition. Following the steps in http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/recognize-expanded-volume-linux.html, we can expand the EBS without stopping the instance. The key steps: 1) Login to AWS Console, locate the EBS and modify the volume size - there is no need to stop the instance (if you are using the current generation of EC2 and EBS - as of Oct, 2017) 2) SSH to the EC2 3) Run lsblk - you will see xvda / xvda1 with different sizes, meaning you need to resize the partition before you can expand the volume 4) Resize the partition - growpart /dev/xvda 1  (note the space between xvda and 1) 5) The resize the filesystem - resize2fs /dev/xvda1 There are other posts saying stopping the instance, and use parted and gdisk. In our case, it is not necessary. There are disadvantages of a using single EBS scenario, but the beauty is that OS/...

Trying to update from older version of ISPConfig 3.x to 3.1. After executing the command: ispconfig_update.sh The upgrade went smooth but upon returning to the login screen, it won't proceed further (it redirects back to the login screen after inputting a pair of valid username and password.) First, try quitting and relaunching the browser (or test with another one). If failed, following these steps: Try re-installing from the source: cd /tmp wget http://www.ispconfig.org/downloads/ISPConfig-3-stable.tar.gz tar xfz ISPConfig-3-stable.tar.gz cd ispconfig3_install/install/ php -q install.php Note during the prompt asking if you want to reconfigure the database, choose "yes".