Can getaddrinfo() be extended to return the record TTL

[Jeff Layton]

On Fri, 2019-08-02 at 17:46 -0400, Carlos O'Donell wrote:
> On 8/2/19 3:33 PM, David Howells wrote:
> > Well, I could put a better/configurable default in the code as a stopgap, so
> > there is a workaround.
> 
> You'll need it.
> 
> For Fedora you're looking at 6-8 months before you see a release with the
> fix in it (unless you use Rawhide or the fix is ABI neutral).
> 
> Then in RHEL you may have to wait around 3 years before there is a rebase to
> an upstream branch.
> 
> Other distributions pickup the changes faster or slower depending on which
> release you use.
> 

Yes. We absolutely will need to deal with new kernel + old userspace
(and vice versa) for a long time, so that needs to be a consideration.

A reasonable default (60s? 5 mins? 12h?) and maybe a tunable of some
sort (sysctl or module param) for that would probably be fine.

You could also printk on the first downcall when userland didn't send a
TTL field, so that the admin knows that he might want to update his
userland eventually.
-- 
Jeff Layton <jlayton@redhat.com>