Syncing Time in CentoOS 7 (ntp/chrony)

For some reason, I couldn't get this to sync until I finally found 1 command that everyone never mentioned.  Here's how to set it up.

ntpd

1. yum install ntp ntpdate
2. systemctl start ntpd
3. systemctl enable ntpd
4. systemctl status ntpd
5. ntpdate -u -s 0.centos.pool.ntp.org 1.centos.pool.ntp.org 2.centos.pool.ntp.org
6. timedatectl set-ntp yes
7. timedatectl set-ntp 1
8. systemctl restart ntpd

chronyd

1. yum install chrony
2. systemctl enable chronyd
3. systemctl start chronyd
4. ntpdate pool.ntp.org
5. timedatectl set-ntp yes
6. timedatectl set-ntp 1
7. systemctl restart chronyd

Source: Link Link Link Link Link

How to unassociated a file type in Redhat/CentOS 7

They are located in:

/home/username/.config/mimeapps.list

Inside you should see the file type.  Remove and save it.  It should go back to how it was originally.

CentOS 7 GDM forces you to create a local account even when using LDAP, NIS, etc

This is a super annoying issue.  Here is how I got around it.

After install switch to tty2 Ctrl+Alt+F2.  Login as root.  Setup your choice of authentication..

Before logging out change this setting.

Edit /etc/gdm/custom.conf

Look for the section that says [daemon]  and add the following:

InitialSetupEnable=false

Save and exit.  Reboot the machine and login.

 Source:  Link

do_ypcall: clnt_call: RPC: Timed Out CentOS 7

I kept getting this error message after installing and configuring NIS.

I ended up figuring out that firewalld was blocking it.  It was also causing ssh and other services to connect really slow.

For now I just did:

systemctl stop firewalld
systemctl disable firewalld

At some point I'll figure out the rule.

Source:  Link