On 23/09/2026 5:04 pm, Vincent Lefevre wrote:
On 2026-09-23 09:53:46 +0700, Max Nikulin wrote:
I believe, it should be prominently documented that it is better to disable
host request cache in nscd and to use some tool designed having in mind
complexity related to DNS: systemd-resolved, dnsmasq.
Or nscd should be fixed. If the libnss API cannot handle partial
failures with AF_UNSPEC, I recall that it is possible to obtain
IPv4 and IPv6 addresses separately (with AF_INET and AF_INET6,
respectively), thus probably detect failures in a more reliable
way. So nscd could do that.
Are there Name Services (notice: not *DNS*, but in broad sense here)
other than "host" (that usually includes DNS among other means for
hostname resolution) where partial failures are possible? If not then I
do not see any point in wasting resources for redesigning libnss and for
rewriting its plugins (including 3rd party and internal ones). I
believe, it is easier to stop using nscd for the "host" service leaving
the tool to the scope where it performs reasonably well.
I suspect, nscd has no notion of AF_UNSPEC, AF_INET, AF_INET6 and
instead it operates on more generic level.
