Re: Low priority question: negative cache in autofs5

[Ondrej Valousek <webserv@s3group.cz>]

Hi Ian,

Thanks for the quick reply. And what is the answer to the first question
please (regarding lstat & wildcard entry)? :-)
It is not he same case I guess....
Many thanks,

Ondrej

Ian Kent wrote:
> On Fri, 2008-12-05 at 12:30 +0100, Ondrej Valousek wrote:
>   
>> Probably to Ian:
>> I am just looking in the autofs5 (from RHEL5) source. I have an indirect
>> nis map:
>> auto.master:
>> /appli auto.appli
>> /proj auto.proj
>>
>> Now, auto.proj contains a wildcard entry (* nfsserver:/share/&) but
>> auto.appli does not.
>>
>> 1. Every time I try to enter (shortly after each other)
>> /proj/nonexistent_directory, I got this:
>> Dec  5 12:10:45 ara automount[3101]: rmdir_path: lstat of
>> /proj/nonexistent_directory failed
>> ... why did not the negative cache save us the expensive call to lstat?
>>
>>
>> 2. Every time I try to enter (shortly after each other)
>> /appli/nonexistent_directory, I got this:
>> Dec  5 12:11:41 ara automount[3101]: lookup_mount: lookup(yp): key
>> "nonexistent" not found in map
>> ... again, looks like the nis daemon was consulted but the negative
>> cache should take the place.
>>     
>
> Known bug with v5 handling of negative caching of non-existent keys.
> I'm working on it but it is proving a little bit tricky because of
> possible multiple map sources listed in nsswitch.conf (at least that's
> where I'm currently at).
>
>   
>> Maybe I do not understand the concept of negative caching well....
>>     
>
> No .. you got it right .. I missed it.
>
> Another thing, there are quite a few changes going into RHEL-5.3 autofs
> which will make their way into RHEL-4.8 in due course. Hopefully you
> will not get caught by them but it is worth logging calls for issues in
> case you are seeing a known issue.
>
> Ian
>
>