Manually setting a hostname

A substantial dependency of oneSIS is that the node's hostname must have already been set when rc.preinit runs at boot time. For this reason the hostname for diskless nodes is normally set (via the use-host-decl-names option in DHCP) in an initramfs prior to running /sbin/init.

There are alternatives that may prove useful for diskful nodes running an initramfs supplied by the distribution (which typically do not set a hostname), some other initramfs not created by oneSIS, or when using a NODHCP configuration (section 3.3.2).

If a node reaches rc.preinit without having a hostname set, oneSIS can determine it from the first of the following methods (in order) which succeeds:

1. By consulting a list of MAC_ADDR directives (subsection 5.11.1).
2. From a hostname= parameter on the kernel command line.
3. By looking in /etc/hosts for the address specified by a kernel command line ip= parameter (this requires that /etc/hosts is not the target of a LINKBACK and contains entries for all the oneSIS nodes).
4. By reading it from /etc/oneSIS/hostname, which can be set after deploying a diskful node.