Stateful Load Balancer with iptables and NAT Rumi, October 2, 2018October 2, 2018 Allow IP forwarding (Note: if your testing this on the same box your doing this on it won’t work, you need at least 3 machines to test this out, virtual ones work nicely) First we enable ipv4 forwarding or this will not work: # echo “1” > /proc/sys/net/ipv4/ip_forward XOR #… Continue Reading
Assign range of IP addresses to an interface Rumi, October 2, 2018 For example, you need to assign the IP range 192.168.10.6 – 192.168.10.100 to your eth0 interface. Create a range file in /etc/sysconfig/network-scripts/ifcfg-eth0-range0 as below DEVICE=eth0 BOOTPROTO=static IPADDR_START=192.168.10.6 IPADDR_END=192.168.10.100 NETMASK=255.255.255.0 CLONENUM_START=1 ONBOOT=yes TYPE=Ethernet CLONENUM_START is the number that will be assigned to the first IP alias interface (eth0:1 in this example)…. Continue Reading
Reset CentOS Root Lost or Forgotten Password Rumi, September 21, 2018 In the event your Linux box experiences disk or file system issues you may receive a “Give root password for maintenance” prompt upon reboot. If you have your root password you can login but in the event your using ‘slide’ or ‘sudo’ for wheel access or you’ve just mis-placed your… Continue Reading
Install Cacti 1.1 on CentOS 7 Rumi, September 2, 2018 Cacti is a free and open source network monitoring and graphing tool written in PHP. With the help of RRDtool (Round-Robin database tool), Cacti can be used to provide various useful features, including remote and local data collectors, graph templating, network discovery, device management automation, etc. Prerequisites A fresh CentOS… Continue Reading
Mail Sync between 2 mailservers using Imapsync Rumi, May 12, 2018May 12, 2018 Imapsync is an IMAP transfer tool used for copying emails from one IMAP server to another IMAP server. This article will help you to install imapsync on Ubuntu, Debian, and LinuxMint systems and transfer all your Mailboxes and emails between two IMAP servers. Step 1 – Install Imapsync Imapsync package… Continue Reading
Linux Router- No NAT Rumi, May 7, 2018 I assume you have one public IP address for your WAN side, and a block for the LAN side, something like this: ISP—–ROUTER ETH0/ROUTER ETH1——SWITCH——PCs You NEED to have a public IP address for the WAN interface, ISP will route the subnet they have given you through this IP address…. Continue Reading
Install iRedmail on a CentOS 6.8 server Rumi, March 17, 2018June 10, 2018 We need to set a FQDN hostname before we set up the mail server. On CentOS Linux, hostname is set in two files: Hostname setting: nano /etc/sysconfig/network # Part of file: /etc/sysconfig/network HOSTNAME=demo.iredmail.org Hostname <=> IP address mapping: /etc/hosts. WARNING: Please list the FQDN hostname as the first item. # Part of… Continue Reading
Install Mailtrain Bulk Mailer Application on CentOS 7 Rumi, March 17, 2018March 17, 2018 Requirements Metabase requires at least 1GB of RAM. All the required dependencies will be installed throughout the tutorial. You will need a minimal installation of CentOS 7 with root access on it. If you are logged in as a non-root user, you can run sudo -i to switch to root… Continue Reading
Build NFS Server on CentOS 7 Rumi, March 9, 2018 As the first step, we will install these packages on the CentOS server with yum: yum install nfs-utils Now create the directory that will be shared by NFS: mkdir /var/nfsshare Change the permissions of the folder as follows: chmod -R 755 /var/nfsshare chown nfsnobody:nfsnobody /var/nfsshare We use /var/nfsshare as shared folder, if we… Continue Reading
Postfix start error on CentOS Rumi, March 7, 2018 When I tried to start postfix today, I got the following message: fatal: parameter inet_interfaces: no local interface found for 1.2.3.4 Solution is straightforward: nano /etc/postfix/main.cf comment out “inet_interfaces = all” add “inet_protocol = ipv4” Continue Reading