This guide assumes you have a working Postfix server and want it to sign with DKIM.
There are a few things we have to understand to make all of this work though, which require you to be familiar with DNS as well.
1.) Install OpenDKIM
apt install opendkim
systemctl enable opendkim
2.) Edit /etc/opendkim.conf
Syslog yes
SyslogSuccess yes
Mode&nbs........
You'll have to violate the iso9660 standards but it is necessary if you want to preserve your filesystem and filenames and shouldn't be an issue as long as you are using a modern OS like Linux.
genisoimage -o Backup-Myfiles.iso -r -J -joliet-long /some/path/
You will get errors like below (even enabling joliet-long didn't help)
genisoimage: Error: /some/filename.pdf have the same Joliet name
Joliet tree sort failed. The -joliet-lo........
Very simple browse to your /boot directory
It does make more sense to extract the image in its own directory eg "initramfs-blabla-dir" as it will literally extract directly to the pwd.
cp initramfs.img someotherdir
cd someotherdir
zcat initramfs-3.10.0-514.el7.x86_64.img | cpio -idmv........
Setup Static IP Address ONBOOTAssuming you are using eth0
Note this will work for any version of CentOS and basically any version of Redhat Linux or Redhat based distribution.
You would need to create a new file
[code:1:02f8d34c30] /etc/sysconfig/network-scripts/ifcfg-eth0:0[/code:1:02f8d34c30]
DEVICE=eth0:0
the ":0" at the end specifies alias 0 we could actually change this to ":99" or "........