I'm trying to set up Bind. Here I add the user named for Bind.

All of these were used as Root.

useradd -r -d /var/named -s /sbin/nologin named

Here I create the chroot jail.
rm -rf /var/named

Make my directories.
mkdir -p /var/named/chroot/dev
mkdir -p /var/named/chroot/etc
mkdir -p /var/named/chroot/var/run
mkdir -p /var/named/chroot/var/named

Now comes the ERROR.

Here I'm trying to give the proper permissions to the directories.

When I run this:
chown -R root:named /var/named

I get this error: chown: root:named : invalid group
What am I doing wrong?

When I'm doing these I am at:
xyz:~ #

You never created a group named, just a user named. man addgroup will help you.

The statement "chown -R root:named /var/named" makes user root of group named the owner of those directories recursively. You need to create the group named, or make named:users the owners.

Peace,
JimBass

Makes sense now.

Would Named group be a system group?

I don't know what you mean by "system group". Groups are just like users, they exist everywhere on the computer. I think groups came about because of security. You needed cases where every member of group A would need read and write access to file Z, yet if the file was owned by any single member of the group, say person M, then the only way things would work would be if the permissions were set to world-writable, which is very dangerous. The group acts as a buffer. Every member of group A gets the second set of permissions on a file. That way a permission of 664 on a file owned by root:named means root (the owner) can read and write, named (the group) can read and write, and everyone else can read, but not write. Obviously not everyone can be root, but if your user has membership in group named, then you also have permission to write to the file.

Checkout the security model, particularly permissions for users and groups, and post back with any questions.

Peace,
JimBass