fqdn

Following up to Regular expression to match hostname or IP Address? and using Restrictions on valid host names as a reference, what is the most readable, concise way to match/validate a hostname/fqdn (fully qualified domain name) in Python? I've answered with my attempt below, improvements welcome. Tim Pietzcker import re def is_valid_hostname(hostname): if len(hostname) > 255: return False if hostname[-1] == ".": hostname = hostname[:-1] # strip exactly one dot from the right, if present allowed = re.compile("(?!-)[A-Z\d-]{1,63}(?<!-)$", re.IGNORECASE) return all(allowed.match(x) for x in

Is there a quick and dirty way to validate if the correct FQDN has been entered? Keep in mind there is no DNS server or Internet connection, so validation has to be done via regex/awk/sed. Any ideas? John Nagle It's harder nowadays, with internationalized domain names and several thousand (!) new TLDs. The easy part is that you can still split the components on ".". You need a list of registerable TLDs. There's a site for that: https://publicsuffix.org/list/effective_tld_names.dat You only need to check the ICANN-recognized ones. Note that a registerable TLD can have more than one component,

How can you get the FQDN of a local machine in C#? Mike Dinescu NOTE: This solution only works when targeting the .NET 2.0 (and newer) frameworks. using System; using System.Net; using System.Net.NetworkInformation; //... public static string GetFQDN() { string domainName = IPGlobalProperties.GetIPGlobalProperties().DomainName; string hostName = Dns.GetHostName(); domainName = "." + domainName; if(!hostName.EndsWith(domainName)) // if hostname does not already include domain name { hostName += domainName; // add the domain name part } return hostName; // return the fully qualified name }