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This is still how it works today, because we're always using >>> the default value anyway, but should someday this be fixed, then we can >>> go back to rely on the keys infrastructure to cache each hostname with >>> its own separate TTL. >> >> Curious, why did you choose a procfs global approach? Wouldn't it be >> more appropriate to make this a mount option, so it would be applied >> selectively per-server? > > I tried to stick to the current behaviour, while also fixing the issue > of getting a TTL=0 from key.dns_resolver upcall. > > A mount option looks indeed better initially, and that was also my > initial approach to this. But in a, e.g. multi-domain forest, with > multiple DFS targets, the per-mount setting starts to look irrelevant > again as well. So I took the "per-client" approach instead. Ok, I guess. It seems like kicking the can down the road, a little. I agree that rearchitecting the DNS cache might be extreme, but many distros consider procfs to be a user API, and they'll require it to be supported basically forever. That would be unfortunate... Tom.