Created
April 27, 2018 21:30
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Test overlay multiple depths
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#!/bin/sh | |
set -x | |
tempdir=$(mktemp -d) | |
oldpwd=$(pwd) | |
function cleanup() { | |
cd $oldpwd | |
umount -fR $tempdir | |
sleep 1 | |
rmdir $tempdir | |
} | |
trap cleanup EXIT | |
mount -t tmpfs tmpfs $tempdir | |
cd $tempdir | |
mkdir source-{1,2,3,4,5,6} mnt-{1,3,5} upper work mnt | |
# Layer/files | |
# L / 1 2 3 4 5 6 | |
# 1 | 1 | |
# 2 | 2 2 | |
# 3 | 3 3 3 | |
# 4 | 4 4 4 4 | |
# 5 | 5 5 5 5 5 | |
# 6 | 6 6 6 6 6 6 | |
for i in {1..6}; do echo "6" > source-6/$i; done | |
for i in {1..5}; do echo "5" > source-5/$i; done | |
for i in {1..4}; do echo "4" > source-4/$i; done | |
for i in {1..3}; do echo "3" > source-3/$i; done | |
for i in {1..2}; do echo "2" > source-2/$i; done | |
echo "1" > source-1/1 | |
mount -t overlay -o "ro,lowerdir=$tempdir/source-5:$tempdir/source-6" overlay mnt-5 | |
mount -t overlay -o "ro,lowerdir=$tempdir/source-3:$tempdir/source-4" overlay mnt-3 | |
mount -t overlay -o "ro,lowerdir=$tempdir/source-1:$tempdir/source-2" overlay mnt-1 | |
# Lower directories cannot themselves have overlays as lower directories | |
# For example, the following is not allowed | |
#mount -t overlay -o "ro,lowerdir=$tempdir/source-2:$tempdir/mnt-3" overlay mnt-2 | |
#mount -t overlay -o "ro,lowerdir=$tempdir/source-1:$tempdir/mnt-2" overlay mnt-1 | |
mount -t overlay -o "rw,lowerdir=$tempdir/mnt-1:$tempdir/mnt-3:$tempdir/mnt-5,upperdir=$tempdir/upper,workdir=$tempdir/work" overlay mnt | |
set -e | |
for i in {1..6}; do test $(< mnt/$i) = "$i"; done |
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