openssh unix dev - Dec 2020 - ssh_config: Hostname with multiple IP addresses

Hi folks,

ssh_config(5) explicitly allows numeric IP addresses (plural) on the
Hostname config line in .ssh/config, but it doesn't tell the syntax.
Neither

	Hostname 10.0.0.1 2001:db8::1
nor
	Hostname 10.0.0.1,2001:db8::1
nor
	Hostname 2001:db8::1
	Hostname 10.0.0.1

seem to work.

How is this supposed to be written? Would you mind to improve the man
page?


Thanx in advance
Harri

On 11/12/2020 08:42, Harald Dunkel wrote:
> ssh_config(5) explicitly allows numeric IP addresses (plural) on the
> Hostname config line in .ssh/config,
Can you point to where it says that explicitly? I see in ssh_config(5):

 ???? HostName
 ???????????? Specifies the real host name to log into.

Note that "real host name" is in the singular.

It then does make use of the plural:

 ???? This can be used to specify nicknames or abbreviations for hosts

but I read that as meaning that you can configure multiple hosts, each 
with its own HostName, e.g.

Host foo
HostName 192.0.2.1

Host bar
HostName 192.0.2.2

Similarly:

 ???? Arguments to HostName accept the tokens described in the TOKENS 
section.? Numeric IP addresses are also permitted

To me this is talking about multiple HostName entries in the same 
ssh_config file, each belonging to a different Host, rather than one 
HostName allowing multiple IP addresses. However I guess it could be 
read either way.