Page History

...

1. Install CentOS 7 using either the Minimal or the DVD ISO available here (available on the SLAC network or VPN).  The ISO image can also be used for a USB key install.

   http://yum.slac.stanford.edu/iso/centos/7

    

2. Log into your new CentOS 7 host. 
   Become root by using sudo or /bin/su. 
   Install Chef on bare metal or a VM by running this command as root:

   curl -s http://yum.slac.stanford.edu/go-chef | /bin/sh

   If you want to only configure yum, and not run any of the other Chef recipes, then don't run the above command, run this instead:

   curl -s http://yum.slac.stanford.edu/go-chef  |  sed -e 's/^chef-client.*/chef-client -r recipe[slac_yum]/'  |  /bin/sh

   That command is using 'sed' to replace the last line of the go-chef script.  Note these instructions are subject to frequent change, so please check back to this page for the most recent version. Configuring only yum, and nothing else, means that your CentOS 7 host is unmodified except it can now apply yum updates, even if your machine is on a private 172.X subnet.
   

    

   
   
   

3. After you have run one of the above curl commands, you can optionally install the AFS client. Do not install the AFS client unless you have to. AFS is optional for CentOS 7 and it is not required to have a centrally manged CentOS 7 host. The default CentOS 7 host will not have AFS installed, but it is available if you require it. Here is the command to install it:

   chef-client -o slac_openafs

   This recipe takes a long time to run since it compiles an openafs kernel module for the running kernel.  The openafs client will start automatically – no reboot is required. You will not automatically get an afs token when logging in.  Run the following command to get an afs token:

   aklog

   If you want to leave your home directory alone (ie, keep it on the local disk) then you are done.  But if you want to have your AFS home directory as your home directory on this machine when you login, here are the steps to do that:

   Edit this file: /etc/sssd/sssd.conf
   
   comment out the line that says:
   override_homedir = /home/%u
   Run this command:
   systemctl restart sssd
   
   Create a symlink by running this command:
   ln -s /afs/slac.stanford.edu/u /u
   
   You should now have this symlink:
   /u -> /afs/slac.stanford.edu/u
   
   logout and login - and you should be in your AFS home directory, but you still need to run 'aklog' to get an AFS token after logging in.
   
   
   

4. Before you exit your root prompt, you need to modify this file:
   /etc/security/access.netgroup.conf
   
   Add a line that looks like this (replace 'ksa' with your username):
   +

   :

   ksa

   :

   ALL
   
   Make sure to add that line above the last line.  Here is an example of what the file might look like if you wanted to grant login access to SLAC users ksa and vanilla:
   
   + : root : LOCAL  134.79.0.0/16 172.16.0.0/12
   + : ksa : ALL
   + : vanilla : ALL
   + : @u-scs-staff : ALL
   - : ALL : ALL 
   
   
   

5. And still before you exit your root prompt, create a sudoers entry for yourself inside the /etc/sudoers.d directory.
   If you do not want or need sudo access, you can skip this step.
   
   You can copy and paste the following (replace 'ksa' with your username):
   cat

   >

   /etc/sudoers.d/user-ksa

   <<

   EOF
   ksa  

   ALL=ALL
   EOF
   
   Be sure to read and fill out the sudo request form.  This is required for auditing purposes:
   https://www.slac.stanford.edu/comp/unix/auth/superuser-req.shtml 
   
   
   

6. If you would like a Kerberos host keytab installed on your CentOS 7 host, send an email to unix-admin@slac.stanford.edu .
   
   Without a Kerberos host keytab, you will need to enter your SLAC password when connecting via ssh, even when you already have a Kerberos ticket granting ticket (TGT).  If you have unix-admin install a Kerberos host keytab, then you can use passwordless GSSPAI via ssh to connect without a password when you already have a Kerberos TGT.
   
   
   

...

Soon we will run the chef client as a daemon, but at the moment the go-chef command is a one-time configuration script, which will not install a cron job or a daemon to run chef periodically.  This is because we do not want to overwrite the access.netgroup.conf file and remove any modification you have made to the user login list.  Soon we will have your user login list maintained by Chef, but we are still working on that now.

...