starlingx/tools
Code Issues Proposed changes

download_mirror.sh fails with 404 errors

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The 'yum makecache' step is failing. The issue is seen when the fast
mirror plugin for yum is in use (default).

The metadata for a yum repo as scattered across several files. The
master file is repomd.xml, and it may list several supporting files,
e.g.
   filelists.xml.gz
   primary.xml.gz
   filelists.sqlite.bz2
   other.sqlite.bz2
   other.xml.gz
   primary.sqlite.bz2

When fast mirror plugin is in use, each file might download from a
separate source. This opens the door for a race condition when a repo
update is rolling out across the mirrors.

The error suggests we have already downloaded a repomd.xml, but it is
obsolete and references a supporting file that no longer exists.

A second possible source of inconsistent data is caching proxies.

Solution:
1) Disabling the yum fast cache plugin is undesirable, and there
is no option forcing metadata iof a given repo to be single sourced.
So this update adds a limited number of retries for the
'yum makecache' command.

So far we've never seen 'yum makecache' fail twice in a row... 
largely because the 'fastest mirror' plugin rarely downloaded from the
same source twice.

2) Add 'http_caching=packages' to yum.conf, which asks upstream proxies
to not cache repodata.

Change-Id: I3fa3f61e38d868fb14f4175b87c0d323abb57def
Closes-bug: 1818911
Signed-off-by: Scott Little <scott.little@windriver.com>
This commit is contained in:
Scott Little 2019-03-06 16:47:22 -05:00
parent eecfe6ed5e
commit cf435e6c2a
3 changed files with 21 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Dockerfile
View File

@ -21,6 +21,8 @@ FROM centos:7.4.1708
# echo -e "export http_proxy=$http_proxy\nexport https_proxy=$https_proxy\n\
#export ftp_proxy=$ftp_proxy" >> /root/.bashrc
RUN echo "http_caching=packages" >> /etc/yum.conf
# username you will docker exec into the container as.
# It should NOT be your host username so you can easily tell
# if you are in our out of the container.

19
centos-mirror-tools/dl_rpms.sh
View File

@ -251,7 +251,24 @@ download () {
# Prime the cache
${SUDOCMD} yum ${YUMCONFOPT} ${RELEASEVER} makecache
loop_count=0
max_loop_count=5
echo "${SUDOCMD} yum ${YUMCONFOPT} ${RELEASEVER} makecache"
while ! ${SUDOCMD} yum ${YUMCONFOPT} ${RELEASEVER} makecache ; do
# To protect against intermittent 404 errors, we'll retry
# a few times. The suspected issue is pulling repodata
# from multiple source that are temporarily inconsistent.
loop_count=$((loop_count + 1))
if [ $loop_count -gt $max_loop_count ]; then
break
fi
echo "makecache retry: $loop_count"
# Wipe the inconsistent data from the last try
echo "yum ${YUMCONFOPT} ${RELEASEVER} clean all"
yum ${YUMCONFOPT} ${RELEASEVER} clean all
done
# Download files
if [ -s "$rpms_list" ];then

1
centos-mirror-tools/yum.conf.sample
View File

@ -13,6 +13,7 @@ bugtracker_url=http://bugs.centos.org/set_project.php?project_id=23&ref=http://b
distroverpkg=centos-release
override_install_langs=en_US.utf8
tsflags=nodocs
http_caching=packages
reposdir=yum.repos.d