starlingx
/
config
Code Issues Proposed changes

Fix run_docker_login DNS lookup to handle misconfigured nameservers 

A customer added a non-existant nameserver and it resulted in an edge case
that broke the previous code.  (dig returned 9 even though it found an
AAAA record for the name.)

It looks like we're going to need to bite the bullet and explicitly issue
separate requests for IPv4 and IPv6.

Partial-Bug: 1886121
Change-Id: I8d653a82a2aee0a86af587f6392277974c9f1fef
Signed-off-by: Chris Friesen <chris.friesen@windriver.com>
This commit is contained in:
Chris Friesen 2020-07-22 18:01:07 -04:00
parent 63d97f96da
commit 133eb1d450
1 changed files with 24 additions and 5 deletions
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29
sysinv/sysinv-fpga-agent/run_docker_login
View File

@ -21,10 +21,14 @@ function LOG {
LOG "Waiting for registry.local to resolve"
while true
do
# This will ask for both A and AAAA records to handle IPv4 and IPv6.
# We don't want to do an ANY request because some DNS servers reject
# them and they can return way more data than we actually want.
ADDR=`dig +short registry.local A registry.local AAAA`
# We can't easily ask for both A and AAAA records in the same request
# because if the customer mis-configures things with a "good" nameserver
# and a non-existant nameserver dig will return "9" even though it finds
# an AAAA record on the "good" server. So we need to ask for A and AAAA
# records separately. Once we have either type of record we can proceed.
# First check for A records for IPv4
ADDR=`dig +short registry.local A`
if [ $? -eq 0 ]
then
# We got a response back from the server, but we need to check
@ -32,10 +36,25 @@ do
# be an empty string.
if [ -n "$ADDR" ]
then
echo LOG "registry.local resolved, continuing with docker login"
echo LOG "registry.local resolved IPv4, continuing with docker login"
break
fi
fi
# Then check for AAAA records for IPv6
ADDR=`dig +short registry.local AAAA`
if [ $? -eq 0 ]
then
# We got a response back from the server, but we need to check
# if we got an address or not. If there is no address, ADDR will
# be an empty string.
if [ -n "$ADDR" ]
then
echo LOG "registry.local resolved IPv6, continuing with docker login"
break
fi
fi
sleep 1
done