How To Enable Legacy Key Type Support in SSH 7

Author: , December 9th, 2016

Recently I had to launch an Ubuntu instance in AWS because i needed to run alien to convert a .rpm into a .deb package. When I added my SSH keys as usual, I found I was still unable to login. This is the error from the /var/log/auth.log file: Dec 9 16:47:55 localhost sshd[1550]: userauth_pubkey: key […]

How To Fix apt-get Errors on Old Ubuntu Hosts

Author: , August 3rd, 2016

As usual, whenever I have to do sysadmin on a Ubuntu-based OS, I find problems. When will people realize what a horrible OS it is? In this case, packages needed were unavailable. For apt-get to function, the file /etc/apt/sources.list must be edited to change all URLs from and to, using the sed […]

How To Find the Ubuntu Distribution Version

Author: , April 8th, 2014

$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 12.04.2 LTS Release: 12.04 Codename: precise $ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=12.04 DISTRIB_CODENAME=precise DISTRIB_DESCRIPTION=”Ubuntu 12.04.2 LTS”

How To Reload sysctl.conf in Ubuntu

Author: , October 7th, 2013

sysctl -p /etc/sysctl.conf

How To Disable iptables Completely

Author: , October 2nd, 2013

List current iptables entries: iptables -L /etc/init.d/firewall stop ~or~ /etc/init.d/iptables stop ~or~

How To Increase the Open Files ulimit on Ubuntu

Author: , April 29th, 2013

Add the following four lines to the bottom of /etc/security/limits.conf: root soft nofile 65535 root hard nofile 65535 * soft nofile 65535 * hard nofile 65535 NOTE: All whitespace MUST be a single tab! Also edit these three files: /etc/pam.d/su /etc/pam.d/common-session /etc/pam.d/common-session-noninteractive and add the following one line: session    required

How To Add AWS EC2 API Tools to Ubuntu AMI Instance

Author: , March 28th, 2013 As root in /root: vim /etc/apt/sources.list ## Added to the bottom: deb hardy multiverse deb-src hardy multiverse deb hardy-updates multiverse deb-src hardy-updates multiverse apt-get update apt-get install sun-java5-jre apt-get install unzip wget unzip export EC2_HOME=/root/ec2-api-tools-1.3-34128 export PATH=$PATH:$EC2_HOME/bin mkdir .pem Copy downloaded X.509 private key and cert into […]