Posts in Category: SysAdmin
Proxy using SSH Tunnel
How to auto start services on boot in Centos / Redhat / Oracle Linux?
To auto start services in Centos, Redhat or Oracle Linux, you can use builtin chkconfig utility. It is located in /sbin directory. If you are a regular user (non-root), then /sbin may not be in your path. Therefore, you may have to use the full path to access the chkconfig utility.
AWS lowers cloud pricing by launching the T2 instance type that can burst to handle occasional workload spike
T2 instances are Burstable Performance Instances that provide a baseline level of CPU performance with the ability to burst above the baseline. The baseline performance and ability to burst are governed by CPU Credits. Each T2 instance receives CPU Credits continuously at a set rate depending on the instance size. T2 instances accrue CPU Credits when they are idle, and use CPU credits when they are active. T2 instances are a good choice for workloads that don’t use the full CPU often or consistently, but occasionally need to burst (e.g. web servers, developer environments and small databases).
htop
htop is an interactive text-mode system-monitor process viewer for GNU/Linux. It aims to be a better ‘top’. It shows a frequently updated list of the processes running on a computer, normally ordered by the amount of CPU usage. Unlike top, htop provides a full list of processes running, instead of the top resource-consuming processes. htop uses color and gives visual information about processor, swap and memory status.
Simplify your life with SSH config file and ClusterSSH
If you’re anything like me, you probably log in and out of a half dozen remote servers on a daily basis. And if you’re even more like me, you have trouble remembering all of the various usernames, remote addresses and command line options for things like specifying a non-standard connection port or forwarding local ports to the remote machine. And sometimes you have to do the same thing in a lot of servers, this post is for you.
Apache restrict access based on IP address to selected directories
Apache web server allows server access based upon various conditions. For example you just want to restrict access to url http://subdomain.domain.com/ (mapped to /var/www/subdomain directory) from 192.168.1.0/24 network (within intranet).
Apache provides access control based on client hostname, IP address, or other characteristics of the client request using mod_access module.
How to solve “Falling back to the standard locale” in ubuntu
Sometimes you can get a error like this:
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LC_PAPER = “pt_BR.UTF-8”,
LC_ADDRESS = “pt_BR.UTF-8”,
LC_MONETARY = “pt_BR.UTF-8”,
LC_NUMERIC = “pt_BR.UTF-8”,
LC_TELEPHONE = “pt_BR.UTF-8”,
LC_IDENTIFICATION = “pt_BR.UTF-8”,
LC_MEASUREMENT = “pt_BR.UTF-8”,
LC_TIME = “pt_BR.UTF-8”,
LC_NAME = “pt_BR.UTF-8”,
LANG = “en_US.UTF-8”
are supported and installed on your system.
perl: warning: Falling back to the standard locale (“C”).
Press continue reading to understand how to fix this!
Powerful Redmine in AWS
In this post i will show how to make a installation of Redmine in AWS with some nice tools from AWS (EC2, RDS, S3, SES, ElastiCache) and making it auto scalable.
Amazon SES – Simple Email Service
Amazon Simple Email Service (Amazon SES) is a highly scalable and cost-effective bulk and transactional email-sending service for businesses and developers. Subscription is quick and is on pay-as-you-go basis. 
How to use different user and group for just one Virtual Host in Apache
With the mpm-itk that is a multi-processing module (MPM) you can run each virtualhost with it’s own user id and group id. This is basically used to make a shared hosting secured, since you don’t have to make all virtualhosts folders readeable by apache user.
mpm-itk is based on the traditional prefork MPM, which means it’s non-threaded; in short, this means you can run non-thread-aware code (like many PHP extensions) without problems.