If you have a missing default gateway on your Redhat system you can add new route as per network interface or globally. Defining default gateway using ifcfg files, that is, defining it as per network interface basis takes a precedence over global system wide default gateway configuration defined by /etc/sysconfig/network configuration file.

First, list our routing table with routel command:
[root@rhel7 ~]# routel
         target            gateway          source    proto    scope    dev tbl
      10.0.0.0/ 8                        10.1.1.56   kernel     link enp0s3 
       10.0.0.0          broadcast       10.1.1.56   kernel     link enp0s3 local
      10.1.1.56              local       10.1.1.56   kernel     host enp0s3 local
 10.255.255.255          broadcast       10.1.1.56   kernel     link enp0s3 local
      127.0.0.0          broadcast       127.0.0.1   kernel     link     lo local
     127.0.0.0/ 8            local       127.0.0.1   kernel     host     lo local
      127.0.0.1              local       127.0.0.1   kernel     host     lo local
127.255.255.255          broadcast       127.0.0.1   kernel     link     lo local

Apart of the regular local Redhat's installation, the Redhat system allows admin to modify boot options to temporarily setup network interface and instruct the installation program Anaconda to initiate installation via VNC. In this article we will modify default Redhat's boot options to initiate remote installation using VNC.

First insert installation image and boot into a Redhat's boot options screen as show below:
Redhat 7 boot screen - enter vnc and network options

On this screen we need to modify boot options to instruct the installation program Anaconda to provide us with VNC interface after the end of the boot sequence. Depending whether you use DHCP on your network you can either set static address or do not include any network options for dynamic IP address assignment. In the above screen we have included the following options after pressing "TAB" on the main ( first ) boot option:
ip=10.1.1.56 - optional
netmask=255.0.0.0 - optional
vnc - required

Introduction

Most of the time as a system administrator you are managing your servers over the network. It is very rare that you will need to have a physical access to any of your managed servers. In most cases all you need is to SSH remotely to do your administration tasks. In this article we will configure a GUI alternative to a remote access to your RHEL server, which is VNC. VNC allows you to open a remote GUI session to your server and thus providing you with a full graphical interface accessible from any remote location.

Installation of VNC server

In order to enable an access to our Redhat Linux system using VNC we first need to install it. Make sure that you have your repository enabled and execute the command:

# yum install tigervnc-server

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