Creating multiple web apps in 443 port number

Question

hi all,
 would like to know the speciality of 443 port number.can we create multiple web applns on this ?
assume i have a  web app running on 443 called 
https://myportal.company.com   [  intranet ] can i create a  another web app on this same port, like
https://mysites.company.com [  its a mysite web appln ]  and can we create an all different, Internet web appln on this same port ?
if yes, what are the steps to achieve this.
and curious to know why MSFT has designed like this.
help is appreciated!

Answer 1

Any Web App you create must be differentiated from other Web Apps in one of 3 ways.  It can use a custom IP address, a custom port number or a host header.  In your example you are already using the same port number and I assume you aren't using
different IP addresses since that requires a fair amount of behind the scenes work.  So that would leave creating the two web apps with different host headers.  The problem with this approach is that Apps in SharePoint require at least one web app
in the farm with NO host header.  So if https://myportal.company.com was created using no host header then https://mysites.company.com must be created using a host header.  Any additional Web apps using 443 will also need to be created with host
headers.  Apps will then all run off the MyPortal web app.  You can specify the host header for the web app when creating the web app.  Everything else is normal.
To answer your question of why it is designed this way.  This is the way IIS server works and really has nothing to do with SharePoint.
Paul Stork SharePoint Server MVP
Principal Architect: Blue Chip Consulting Group
Blog: http://dontpapanic.com/blog
Twitter: Follow @pstork
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