include a master file: where does the automounter look

include a master file: where does the automounter look

[Stef Bon]

Hello,

when I read the manpage for auto.master (and other docs) I see that I 
can include another master file by doing:

+auto.master

The comment says that by doing so, the you can specify a master map 
which is found using
nsswitch sources.
What happens then? Where does it look then?

When I add a line with an auto.master file with full path:

+/var/run/autofs/auto.master

it works also.

Stef

Re: include a master file: where does the automounter look

[Ian Kent]

On Mon, 2008-04-28 at 10:32 +0200, Stef Bon wrote:
> Hello,
> 
> when I read the manpage for auto.master (and other docs) I see that I 
> can include another master file by doing:
> 
> +auto.master
> 
> The comment says that by doing so, the you can specify a master map 
> which is found using
> nsswitch sources.
> What happens then? Where does it look then?

If you have a line in /etc/nsswitch.conf like:

automount: files nis

it will look in /etc for auto.master (files) and try to connect to a nis
server and ask for auto.master.

So, it depends on the source specified in /etc/nsswitch.conf.

> 
> When I add a line with an auto.master file with full path:
> 
> +/var/run/autofs/auto.master
> 
> it works also.

That's right.
This just prevents autofs from consulting /etc/nsswitch.conf because it
doesn't need to.

Ian

Re: include a master file: where does the automounter look

[Ian Kent]

On Mon, 2008-04-28 at 16:53 +0800, Ian Kent wrote:
> On Mon, 2008-04-28 at 10:32 +0200, Stef Bon wrote:
> > Hello,
> > 
> > when I read the manpage for auto.master (and other docs) I see that I 
> > can include another master file by doing:
> > 
> > +auto.master
> > 
> > The comment says that by doing so, the you can specify a master map 
> > which is found using
> > nsswitch sources.
> > What happens then? Where does it look then?
> 
> If you have a line in /etc/nsswitch.conf like:
> 
> automount: files nis
> 
> it will look in /etc for auto.master (files) and try to connect to a nis
> server and ask for auto.master.

There's actually a bit more to it than that because of the possibility
of different actions, such as continuing or returning when a source is
found or not.

Ian

Re: include a master file: where does the automounter look

[Stef Bon]

Ian Kent wrote:
> On Mon, 2008-04-28 at 16:53 +0800, Ian Kent wrote:
>   
>> On Mon, 2008-04-28 at 10:32 +0200, Stef Bon wrote:
>>     
>>> Hello,
>>>
>>> when I read the manpage for auto.master (and other docs) I see that I 
>>> can include another master file by doing:
>>>
>>> +auto.master
>>>
>>> The comment says that by doing so, the you can specify a master map 
>>> which is found using
>>> nsswitch sources.
>>> What happens then? Where does it look then?
>>>       
>> If you have a line in /etc/nsswitch.conf like:
>>
>> automount: files nis
>>
>> it will look in /etc for auto.master (files) and try to connect to a nis
>> server and ask for auto.master.
>>     
>
> There's actually a bit more to it than that because of the possibility
> of different actions, such as continuing or returning when a source is
> found or not.
>   
Thanks a lot for the info.

Stef Bon

BTW I'm working on documentating the construction I'm using right now. 
It's not ready, but when I'm happy, I will also
redo the already existing documentation on howtoforge.

Look at:

http://linux.bononline.nl/linux/automountsmbshares/automountsmbshares-page01a.php

Re: include a master file: where does the automounter look

[Ian Kent]

On Mon, 2008-04-28 at 11:12 +0200, Stef Bon wrote:
> Ian Kent wrote:
> > On Mon, 2008-04-28 at 16:53 +0800, Ian Kent wrote:
> >   
> >> On Mon, 2008-04-28 at 10:32 +0200, Stef Bon wrote:
> >>     
> >>> Hello,
> >>>
> >>> when I read the manpage for auto.master (and other docs) I see that I 
> >>> can include another master file by doing:
> >>>
> >>> +auto.master
> >>>
> >>> The comment says that by doing so, the you can specify a master map 
> >>> which is found using
> >>> nsswitch sources.
> >>> What happens then? Where does it look then?
> >>>       
> >> If you have a line in /etc/nsswitch.conf like:
> >>
> >> automount: files nis
> >>
> >> it will look in /etc for auto.master (files) and try to connect to a nis
> >> server and ask for auto.master.
> >>     
> >
> > There's actually a bit more to it than that because of the possibility
> > of different actions, such as continuing or returning when a source is
> > found or not.
> >   
> Thanks a lot for the info.
> 
> Stef Bon
> 
> BTW I'm working on documentating the construction I'm using right now. 
> It's not ready, but when I'm happy, I will also
> redo the already existing documentation on howtoforge.
> 

Did you know I have domain autofs.net.
Some time ago now I started a wiki but never went far enough to make it
usable. http://wiki.autofs.net/ is still responding but is, of course,
light on when it comes to useful doco, and I think out of date.

Ian

Re: include a master file: where does the automounter look

[Stef Bon]

Ian Kent wrote:
> On Mon, 2008-04-28 at 10:32 +0200, Stef Bon wrote:
>   
>> Hello,
>>
>> when I read the manpage for auto.master (and other docs) I see that I 
>> can include another master file by doing:
>>
>> +auto.master
>>
>> The comment says that by doing so, the you can specify a master map 
>> which is found using
>> nsswitch sources.
>> What happens then? Where does it look then?
>>     
>
> If you have a line in /etc/nsswitch.conf like:
>
> automount: files nis
>
> it will look in /etc for auto.master (files) and try to connect to a nis
> server and ask for auto.master.
>   
Ok, it will search for the files first and after that the nis thing.
But here: this line which instructed the automounter to look in the 
nsswitch.conf file is in a auto.master file, and then you instruct it to 
look for the same file again.
This does not make sense to me...

Stef Bon

Re: include a master file: where does the automounter look

[Jeff Moyer]

Stef Bon <stef@bononline.nl> writes:

> Ian Kent wrote:
>> On Mon, 2008-04-28 at 10:32 +0200, Stef Bon wrote:
>>   
>>> Hello,
>>>
>>> when I read the manpage for auto.master (and other docs) I see that I 
>>> can include another master file by doing:
>>>
>>> +auto.master
>>>
>>> The comment says that by doing so, the you can specify a master map 
>>> which is found using
>>> nsswitch sources.
>>> What happens then? Where does it look then?
>>>     
>>
>> If you have a line in /etc/nsswitch.conf like:
>>
>> automount: files nis
>>
>> it will look in /etc for auto.master (files) and try to connect to a nis
>> server and ask for auto.master.
>>   
> Ok, it will search for the files first and after that the nis thing.
> But here: this line which instructed the automounter to look in the 
> nsswitch.conf file is in a auto.master file, and then you instruct it to 
> look for the same file again.
> This does not make sense to me...

The daemon has logic to check for recursion, so it won't include the
same map over and over again.  If it is processing auto.master, and it
sees a +auto.master, it checks the next source in the list.

Cheers,
Jeff