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Ewerton Scaboro da Silva (ewertons) wants to merge 2 commits into
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Give the Android emulator fixed DNS servers #1866

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093acb2
Give the Android emulator fixed DNS servers
Copilot Aug 25, 2026
6dfc1a3
Judge the post-boot check on resolution only, not on ping's exit status
Copilot Aug 25, 2026
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30 changes: 28 additions & 2 deletions vsts/StartEmulator.sh
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Original file line number Diff line number Diff line change
Expand Up @@ -22,8 +22,34 @@ echo "List AVDs:"
$EMU -list-avds

# Start emulator in background and with no UI (-no-window), as we're only running database tests.
nohup $EMU -avd ${NAME_EMU} -no-window -no-snapshot -no-audio -no-boot-anim > /dev/null 2>&1 &
#
# -dns-server is set explicitly because the emulator otherwise resolves through its own DNS proxy, which forwards to
# whatever resolvers the host agent happens to have. On the hosted agents that has proven unreliable: lookups of the
# test hub and provisioning service hostnames intermittently come back as
# java.net.UnknownHostException: Unable to resolve host "...": No address associated with hostname
# for some tests while other tests in the same run resolve the same hostname successfully. Pointing the guest at fixed
# public resolvers takes the host's resolver configuration out of the picture.
nohup $EMU -avd ${NAME_EMU} -no-window -no-snapshot -no-audio -no-boot-anim -dns-server 8.8.8.8,8.8.4.4 > /dev/null 2>&1 &

$ADB wait-for-device
$ADB shell 'while [[ -z $(getprop sys.boot_completed) ]]; do sleep 1; done; input keyevent 82'
$ADB devices
$ADB devices

# Logged so that a DNS failure later in the run can be told apart from an emulator that never had working name
# resolution to begin with. Does not fail the task; the tests report their own failures.
#
# ping's exit status is not used to judge DNS, because it also fails when ICMP is simply not allowed out, which is
# common and harmless here. Only the resolution step is inspected: ping prints the resolved address when the lookup
# succeeded, and reports an unknown host or bad address when it did not.
echo "Checking name resolution from inside the emulator:"
resolutionOutput=$($ADB shell ping -c 1 -W 5 azure-devices-provisioning.net 2>&1)
echo "${resolutionOutput}"

case "${resolutionOutput}" in
*"unknown host"*|*"bad address"*|*"Name or service not known"*|*"Temporary failure in name resolution"*)
echo "WARNING: emulator could not resolve azure-devices-provisioning.net. Name resolution is broken in the guest."
;;
*)
echo "Name resolution succeeded. Any ping failure above is ICMP reachability, not DNS."
;;
esac