Linux and DevOps with Vijay

 [root@rhn ~]# yum install vim bash-completion git gcc openssl-devel wget -y [root@rhn ~]# firewall-cmd --permanent --add-port=80/tcp --add-port=443/tcp --add-port=5647/tcp --add-port=9090/tcp [root@rhn ~]# firewall-cmd --permanent --add-port=8140/tcp --add-port=8443/tcp --add-port=8000/tcp --add-port=67/udp --add-port=68/udp --add-port=69/udp [root@rhn ~]# firewall-cmd --reload [root@rhn ~]# yum install ntp -y [root@rhn ~]# timedatectl set-timezone Asia/Kolkata [root@rhn ~]# ntpdate -u us.pool.ntp.org [root@rhn ~]# rpm -ivh https://fedorapeople.org/groups/katello/releases/yum/3.12/katello/el7/x86_64/katello-repos-latest.rpm [root@rhn ~]# rpm -ivh http://yum.theforeman.org/releases/latest/el7/x86_64/foreman-release.rpm [root@rhn ~]# rpm -ivh https://yum.puppetlabs.com/puppetlabs-release-el-7.noarch.rpm [root@rhn ~]# yum install epel-release -y [root@rhn ~]# yum -y install foreman-release-scl python2-django [root@rhn ~]# rpm -ivh https://yum.puppetlabs.com/puppet/puppet-re

 OpenShift is a cloud development Platform as a Service (PaaS) developed by Red Hat. It is an open source development platform, which enables the developers to develop and deploy their applications on cloud infrastructure. It is very helpful in developing cloud-enabled services. . Openshift as opensource comes with the name OKD from its 3.10 version.(earlier it was known as Openshift Origin) It is a Most demanding technology for hosting micro services in industry. If you wish to explore this technology and want to setup an All in one single node deployment Openshift. Then this article is for you. I have a Virtual Machine on my fedora 29 laptop and i installed Centos 7.6 on it to setup OKD 3.11. I am using a fresh minimal install centos 7.6 so you can follow all steps just after your fresh minimal install . Here are steps : Prepare OS # yum -y install wget git bash-completion net-tools Download Openshift release package # wget https://github.com/openshift/origin/rele

I had a situation in which i setup a nagios server in order to monitor my server hardware and network equipment. I found nagios core to be good sutable for me. I got to setup notification event mails also. I had one isseu in which i could not use phpmail function as all the mails sent were delivered in my junk box. Now i decided to use any smtp service so i selected zoho here. Now the challange was to setup postfx to use zoho smtp in order to send nagios notifications . Here are steps i followed for a successful integration. $ sudo yum install postfix $ sudo nano /etc/postfix/sasl_passwd smtp.zoho.com   [email protected]:password Now post map this credentials and hash them to postfix $ sudo postmap hash:/etc/postfix/sasl_passwd $ sudo chmod 600 /etc/postfix/sasl_passwd  Now edit main.cf file as bellow $ sudo vim /etc/postfix/main.cf relayhost = smtp.zoho.com:465 smtp_use_tls = yes smtp_sasl_auth_enable = yes smtp_sasl_security_options = smtp_tls_wrappermode = yes smt