Re: Examples of local-host-entries or hosts-service-type?

[Remco van 't Veer]

Hi Bruno,

2023/03/02 02:41, Bruno Victal:

> On 2023-02-27 06:23, Remco van 't Veer wrote:
>>
>> Or when you want to provide extra aliases for localhost?
>>
>> Like this?
>>
>>   (essential-services
>>    (modify-services
>>        (operating-system-default-essential-services this-operating-system)
>>      (hosts-service-type config =>
>>                          (list (host "127.0.0.1" "localhost" (list host-name 
>> "foo" "bar"))
>>                                (host "::1"       "localhost" (list host-name 
>> "foo" "bar"))))))
>
> Semantically you're right though I wouldn't outright do this unless it
> results in clearer code or if its really needed.
>
> Reason for this is that the format of /etc/hosts isn't consistently
> defined.
> For instance, there is a limit on the maximum number of
> aliases. (depending on the implementation)
>
> If I wanted to add extra aliases, I'd extend the service with new
> "standalone" host records instead though your snippet is just as
> valid, as long you don't go overboard with the number of aliases.

I not sure all applications will react well to having multiple entries
for the same IP-address.

>From the hosts(5) manpage:

> This file is a simple text file that associates IP addresses with
> hostnames, one line per IP address.

To workaround the alias limit, picking multiple loopback addresses (for
the example above) would be a better solution, it seems.

Cheers,
Remco