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Fix DNS resolution issues in Docker when running in LXD containers#33

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rahulssv-ibm wants to merge 1 commit intoIBM:mainfrom
rahulssv-ibm:fix/dns-docker-lxd
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Fix DNS resolution issues in Docker when running in LXD containers#33
rahulssv-ibm wants to merge 1 commit intoIBM:mainfrom
rahulssv-ibm:fix/dns-docker-lxd

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@rahulssv-ibm
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This pull request enhances network configuration and resolves DNS issues in Docker, particularly when running in LXD containers. The changes include additional netfilter connection tracking settings, disabling bridge netfilter to prevent DNS problems, and configuring fallback DNS servers in Docker daemon.

echo 'ACTION=="add", SUBSYSTEM=="module", KERNEL=="nf_conntrack", RUN+="/usr/sbin/sysctl net.netfilter.nf_conntrack_tcp_be_liberal=1"' | tee -a $netfilter_rule
echo 'ACTION=="add", SUBSYSTEM=="module", KERNEL=="nf_conntrack", RUN+="/usr/sbin/sysctl net.netfilter.nf_conntrack_tcp_loose=1"' | tee -a $netfilter_rule

# Disable netfilter on bridge to prevent DNS issues in Docker (especially in LXD containers)
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Should we check to make sure this is only applied to LXD environment?

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also should these changes be applicable to z runners as well ? or just power ?

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Though it resolves DNS issue, but disabling bridge-nf-call-*tables will affect Kubernetes workflows as they rely on bridge-nf-call-iptables=1. Hence reverting this changes.

@mtarsel mtarsel self-assigned this Apr 14, 2026
…servers

Signed-off-by: Rahul Vishwakarma <Rahul.Vishwakarma2@ibm.com>
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4 participants