Hi Ken, I've posted earlier using "easybeats". This is me "Dex".
I've been reading C source code, plus RHEL documentation to shed some more light If you run the hostname command with an invalid character, IE... hostname invalid\#hostname hostname: the specified hostname is invalid It filters out what it believes to be invalid characters and prints a warning but sets the hostname. Looking at the source code for the "hostname" command (which is the entry point for setting the systems hostname) for Debian, it filters out for alphanumeric, dash (-) and period (.). At the top there is a comment stating it uses the rules from RFC 1034 http://tools.ietf.org/html/rfc1034. (See snippet below) To mean this means that at least for Linux Systems the period (.) is allowed when setting the hostname of the box . IE entries configuration files use the "hostname" command to set the name of the system. /etc/hostname - (Debian) /etc/sysconfig/networking - (Red Hat) Heres the clincher for me, having looked at Red Hats documentation, it was intended "hostname" either the short form (to the first period) or the fqdn (both of which is allowed as the hostname). from http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Installation_Guide/sn-Netconfig-x86.html "Setup prompts you to supply a host name for this computer, either as a fully-qualified domain name (FQDN) in the format hostname.domainname or as a short host name in the format hostname.", notice the period at the end. So my conclusions 1. hostname on Linux was intended as either the FQDN or SHORT FORM (To first period). Periods are allowed in Linux hostname 2. While the hostname fact does not reflect the actual hostname value as held in the Linux kernel (which can contain periods), it does present the correct intepretation of RFC 952. So the "hostname" and "fqdn" facts are strict and correct interpretations of RFC 952, however as stated in a previous post I still maintain that facter should represent the hostname (using a different fact) held as a Linux Kernel C struct value "sysctl -n kernel.hostname" even if it is only part of the fqdn, The example I used was SMTP servers enabling/disabling filtering based on strict RFC interpretations, also the hostname command in Debian doesn't restrict setting of invalid hostnames but warns the user. -Dex -snippet from the hostname command- /* * Check the format of a user-specified hostname. Uses the rules from RFC 1035, * section 2.3.1. */ int check_name(char *name) { int i, len = strlen(name); /* Handle leading and trailing hyphen now. */ if (!len || !isalnum(name[0]) || !isalnum(name[len-1])) return 0; for (i = 0; i < len; i++) { if (!isalnum(name[i]) && name[i] != '-' && name[i] != '.') return 0; if (name[i] == '-' && (name[i - 1] == '.' || name[i + 1] == '.')) return 0; if (name[i] == '.' && name[i - 1] == '.') return 0; } return 1; } -- You received this message because you are subscribed to the Google Groups "Puppet Users" group. To post to this group, send email to puppet-users@googlegroups.com. To unsubscribe from this group, send email to puppet-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/puppet-users?hl=en.
