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[arthurdarcet]

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[BUG | ISSUE]

On startup, FTL tries to close all file descriptors from 0 to ulimit -n (the maximum number of open files) - here https://github.com/pi-hole/FTL/blob/master/dnsmasq/dnsmasq.c#L149

On setups where this limit is high, this takes a large amount of time - or even "hangs" indefinitely. Docker sets this limit to ~1M for instance - and the kubernetes setup I am using (k3s) is setting it to "Infinity", which translates to 1073741816.

I would suggest switching over to something based on the actually open files - like was done for the rpm package: cf https://bugzilla.redhat.com/show_bug.cgi?id=1537564 and https://github.com/rpm-software-management/rpm/pull/444/files for an actual patch

Work around is to run a ulimit -n 1024 before starting FTL in the container - but that's not really a clean solution. (ie add command: [ sh, -c, ulimit -n 1024 && /s6-init ] in the k8s container)

Might be related to pi-hole/docker-pi-hole#561 - I think I was hitting that issue as well

Device specifics

Hardware Type: k3s - kubernetes 1.17 / docker 19.03.6-ce

[DL6ER]

The code you're referring to is the original upstream code of dnsmasq, see: http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blob;f=src/dnsmasq.c;h=573aac069b75b801ad1ddf5305af5010ca1ab88a;hb=HEAD#l151

Any modification to the dnsmasq code needs to be imported from the upstream project to avoid deviations inevitably leading to merge conflicts down the road.

Please contact Simon Kelley over the dnsmasq mailing list for this issue, I'm sure he will have something to say about this: [email protected]

As soon as the dnsmasq projects adopts a code, we can discuss cherry-picking it into our code even before the change is released for the official dnsmasq release.

[arthurdarcet]

Ok thanks - didn't realise that was dnsmasq code. I'll reach out to the dnsmasq ML

[DL6ER]

Just a quick heads up: The code has already landed in FTL (e26f786) and is currently waiting in update/dnsmasq for merging into release/v5.0 when dnsmasq v2.81 is released.