[CentOS] nscd

[Cliff Pratt]

On Tue, Mar 26, 2013 at 12:06 PM, Gary Greene
<ggreene at minervanetworks.com> wrote:
> On Tuesday, Cliff Pratt wrote:
>> On Tue, Mar 26, 2013 at 6:26 AM,  <m.roth at 5-cent.us> wrote:
>>> Has anyone had problems accessing random websites since going up to 6.4?
>>>
>>> Since about the day after I got partly upgraded, if I try to access
>>> nytimes.com, or orbitz.com, I get server not found.
>>>
>>> With a lot of work, I, my manager, and the other admin, found that setting
>>> options edns0 in /etc/resolv.conf fixed it - I suspect that the network
>>> folks updated their internal nameservers (which are M$) about that time...
>>> but... we got this Thurs. Friday, I went to look, lunchtime, at a story,
>>> and back to the same. Later, and I think I was playing around, it came
>>> back.
>>>
>>> Just now, over lunch, it failed... until I restarted nscd. My manager
>>> tells me it's caching... but it seems to be caching momentary failures.
>>>
>>> So: has anyone else seen oddness that might be related to nscd?
>>>
>>Do you want the whole book? 'nscd' is a synonym for weird. I've had
>>many strange DNS issues which have been solved by either bouncing nscd
>>or purging its cache entries.
>>
>> However, you appear to be using nscd on your machine to cache DNS and
>> using the internal MS DSN servers to do the actual lookups. Am I
>> correct? In which case, the MS DNS server should be caching the DNS
>> lookups anyway, so you probably don't derive a lot of benefit from the
>> nscd unless you do a lot of repeated DNS lookups.
>>
>> Cheers,
>>
>> Cliff
>
> NSCD is also necessary if you're running an LDAP or NIS environment,
> so don't just turn it off if you're using external authentication services. In
> a Winbind environment, NSCD is unnecessary however.
>
Ah, yes, indeed. Thanks Gary,

Cliff