Re: [Evolution] 3.16.3: Failed to refresh folder "INBOX",

On Wed, 2015-06-24 at 18:05 +0100, Pete Biggs wrote:
On Wed, 2015-06-24 at 16:59 +0100, Patrick O'Callaghan wrote:
On Wed, 2015-06-24 at 10:38 +0100, Pete Biggs wrote:
command-line ping, dig, or host command returns the new IP for 
name, Evolution should be using that as well.

[[I wish they would fix this line wrapping of quoted content ...]]

Not necessarily, it depends on the individual libraries being 

Strictly that is true, but one would expect a reasonably configured
system to use a single resolver library for everything. Usually 
that is, which is part of glibc.

No, that's just not so, it's much more complex than that.  Most user
programs, like ping, use routines like 'gethostbyname' (or their more
modern equivalent) - those routines get their information from a
variety of sources - /etc/hosts, YP/NIS, DNS - which ultimately might
use libresolv.  Gnome applications tend to use the GIO libraries. 
DNS querying programs like nslookup, host and dig go directly to the
DNS server.

On my system (Fedora 22) nslookup and evolution both link to libresolv,
though ping doesn't.

Things are complicate further by systems such as nscd - "Name Service
Cache Daemon" that, as it says in the man page, "provides a cache for
the most common name service requests" - and that includes hosts. 
default TTL for hosts in nscd is 1 hour.

I stopped using nscd when I moved away from Sun workstations so who

That's why I said in reply to the original poster that you need to be
careful about using things like nslookup to verify DNS entries since
other parts of the system may be caching previous results.

I don't dispute that.


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