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Hostname and Fully Qualified Domain Name ConfigurationΒΆ

Hostname and Fully Qualified Domain Name Configuration

In order to make sure that the Apache server correctly determines the Fully Qualified Domain Name (FQDN) of the server and that the virtual hosts use the correct server URL, the hostname should be configured correctly. This is preferred instead of modifying the Apache server name configuration so that all the software looks to the same source for determining FQDNs. If the command hostname -f returns the correct FQDN hostname then the system is correctly configured to run Open GEE. If not the following instructions may help.

Ideally the network where GEE is installed has a DNS set up to resolve hostnames so that IP traffic can be routed appropriately. However in cases where there is no DNS, static hostnames can be used as well. With static hostnames the hostname or hostnamectl command should be used to set the hostname to its FQDN. The /etc/hostname file should be updated to match as well so the name stays after reboots. If setting the hostname to the FQDN is not possible, then setting the FQDN in the /etc/hosts file is necessary. When using a static hostname, some operating systems may still give a warning on Apache startup even if it correctly determined the FQDN. Adding the FQDN to /etc/hosts would fix this as well. If adding the FQDN to /etc/hosts is needed, then the FQDN followed by just the host portion should be added to the line that contains the IP address the server will be listening on. This should be the first line of the file: myserver localhost

If GEE is not using DNS other clients that connect to the server non-locally would need to have the same static mapping set up in their hosts files since the server hostname would not be resolved dynamically.

When determining where to look for the correct FQDN Apache calls hostname which will use a resolver. The system configuration determines what the order is for resolving the FQDN. If the /etc/nsswitch.conf file is being used there is a line like this that defines the order:

hosts:      dns myhostname files

This example shows that the DNS on the network would be queried first. If that does not define the FQDN then the hostname would be queried. If the FQDN is still not defined then configuration files would be queried, mainly /etc/hosts.

If the /etc/host.conf file is being used to resolve the hostname, then there is a line like this that defines the order:

order hosts,bind

In this example hosts refers to the /etc/hosts file and is checked first, and bind refers to the DNS.

Here is another note on the server hostname.