Dns name resolution rhel
In order to install and configure Anyware Manager or Connector on the RHEL or Rocky Linux machine, it's important to ensure that there is a solid connection between the machine and the Active Directory Domain Controller. You need to ensure that you can route from this machine to the Domain Controller and that there is nothing to prevent port 443 (https) and port 636 (LDAPS) connecting between the two systems.
The following steps are to ensure DNS settings are configured properly on the machine for Anyware Manager or Connector to operate. The sample IP of the Domain Controller is
Disable auto-configuration of DNS settings in order to prevent setting being overwritten on reboot. In this example the device name is
nmcli device modify eth0 ipv4.ignore-auto-dns yes
You may also need to disable this on the connection level in some cases. In this example the connection name is
nmcli connection modify eth0 ipv4.ignore-auto-dns yes
Edit the Network Configuration scripts. Add the
DNS1for the IP address for Active Directory's DNS server (typically the Domain Controller itself) and optionally
DNS2for the fallback DNS server. You can optionally add
DOMAINfor a DNS suffix (typically the Domain name):3. Run the following command to restart the Network Manager:
sudo vi /etc/sysconfig/network-scripts/ifcfg-eth0 TYPE=Ethernet PROXY_METHOD=none BROWSER_ONLY=no BOOTPROTO=dhcp DEFROUTE=yes IPV4_FAILURE_FATAL=no IPV6INIT=yes IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_FAILURE_FATAL=no NAME=ens192 UUID=dfe16427-21f1-429c-99cb-a1e9b42be181 DEVICE=ens192 ONBOOT=yes DNS1=10.162.0.42 DOMAIN=example-domain.com PEERDNS=no4. Check the
sudo systemctl restart NetworkManager
/etc/resolv.conffile to make sure that the desired DNS servers and search suffixes are there. It is important the the
nameserversare the AD DNS or else the machine will fail to connect to the Domain Controller(s):5. Test DNS by pinging the domain, in this example
cat /etc/resolv.conf # Generated by NetworkManager search example-domain.com nameserver 10.162.0.42
example-domain.comis the domain name:6. If the response is successful, you should receive a message similar to the example below:
ping example-domain.com7. Reboot the machine and check that the DNS settings in
PING example-domain.com (10.162.0.42): 56 data bytes 64 bytes from 10.162.0.42: icmp_seq=0 ttl=118 time=16.622 ms 64 bytes from 10.162.0.42: icmp_seq=1 ttl=118 time=50.675 ms 64 bytes from 10.162.0.42: icmp_seq=2 ttl=118 time=27.682 ms 64 bytes from 10.162.0.42: icmp_seq=3 ttl=118 time=19.886 ms ^C --- example-domain.com ping statistics --- 4 packets transmitted, 4 packets received, 0.0% packet loss
/etc/resolv.confpersist and that you can still ping the domain as done in steps 4-6.
Applying Host Machines DNS settings to K3S
The host machine's DNS settings are copied from
/etc/resolv.conf and applied to the Anyware Manager and/or CAS Connector when the CAS K3S service starts. Because of this it is important that settings are correct on boot. You will need to either reboot the machine or restart the K3S service to apply the DNS settings to the Anyware Manager or CAS Connector if changes are made post installation or configuration.
It is best to ensure DNS settings are correct before installing and CAS software on the machine.