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Created by Petr Menšík@pemensikContributor

resolv.conf search parsing has artificial limit

Summary

libirs support only 8 search domains

BIND version used

master branch

Steps to reproduce

  1. sed -i 's/^search .*/search non-existent1.very-long-domain.fedoraproject.org non-existent2.very-long-domain.fedoraproject.org non-existent3.very-long-domain.fedoraproject.org non-existent4.very-long-domain.fedoraproject.org non-existent5.very-long-domain.fedoraproject.org non-existent6.very-long-domain.fedoraproject.org openstacklocal redhat.com/' /etc/resolv.conf
  2. [ "$(host access)" == "$(getent host access.redhat.com.)" ] && echo matches
  3. sed -i 's/^search .*/search non-existent1.very-long-domain.fedoraproject.org non-existent2.very-long-domain.fedoraproject.org non-existent3.very-long-domain.fedoraproject.org non-existent4.very-long-domain.fedoraproject.org non-existent5.very-long-domain.fedoraproject.org non-existent6.very-long-domain.fedoraproject.org non-existent7.very-long-domain.fedoraproject.org non-existent8.very-long-domain.fedoraproject.org openstacklocal redhat.com/' /etc/resolv.conf
  4. [ "$(host access)" == "$(getent host access.redhat.com.)" ] && echo still matches

What is the current bug behavior?

  1. does not match

What is the expected correct behavior?

  1. does match

Relevant configuration files

# resolv.conf
search non-existent1.very-long-domain.fedoraproject.org non-existent2.very-long-domain.fedoraproject.org non-existent3.very-long-domain.fedoraproject.org non-existent4.very-long-domain.fedoraproject.org non-existent5.very-long-domain.fedoraproject.org non-existent6.very-long-domain.fedoraproject.org non-existent7.very-long-domain.fedoraproject.org non-existent8.very-long-domain.fedoraproject.org openstacklocal redhat.com
nameserver 9.9.9.9

Relevant logs and/or screenshots

(none.)

Possible fixes

I know using such high number domains would cause too many queries to resolve. I know it is a bad idea. But I think there should not be such hard limit preventing this. It was updated in glibc to accept unlimited domains. It is not good idea, but I think it is better than simply ignoring what user wishes. We have some customers hitting limits on it.

I think it should be discouraged but possible.

RH Bug for glibc, RH Bug of nslookup

Edited by Petr Menšík