The naming of hosts running SAP software has to be done according to general standards (RFCs see http://ietf.org/rfc) and some SAP specific restrictions.
General rule for hostnames according to RFCs 952, 1101, 1123, 1178:
Alphanumerical string of alpha characters [A-Z] and [a-z] and digits [0-9] and the hyphen (or minus) character "-". Although the newer RFCs permit hostnames beginning with digits we recommend hostnames to begin with an alpha character. The period character "." is only allowed to delimit components of domain names like (sapc11.sap.com).
SAP specific restrictions:
For hostnames of servers running SAP software the following additional restrictions must be obeyed:
- Maximum length of the hostname:
up to 13 characters for SAP rel. 4.6 or higher
up to 8 characters for SAP rel. up to 4.5
- Due to a problem in the installation routine, the host name of computers running Microsoft Windows must not begin with S-[0-9] (e.g. hostname S-12345 is not allowed). Please see SAP note 998631 for further information.
- When using Oracle on Windows see note 849423 for restrictions.
- Hostnames must be considered "case sensitive". That means hostnames shall be used in the same case (upper or lower) in all SAP configurations as well as in the network configuration (DNS or etc/hosts). You must ensure consistent name resolving of the hostname from hostname to IP address and back from the IP address to the the same hostname (case sensitive match). See also note 129997.
- On multihomed hosts the hostname must be assigned to the IP address of the primary network interface. See also note 21151.