From 4f6ebfc537b2d3671112a54873081685d47066db Mon Sep 17 00:00:00 2001 From: David Vossel Date: Fri, 18 Jul 2014 12:31:55 -0400 Subject: [PATCH] Low: LVM: Warn users about the danger of lvmetad --- heartbeat/LVM | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/heartbeat/LVM b/heartbeat/LVM index 4378cd3..27cdfbd 100755 --- a/heartbeat/LVM +++ b/heartbeat/LVM @@ -545,6 +545,25 @@ LVM_validate_all() { check_binary $AWK ## + # lvmetad is a daemon that caches lvm metadata to improve the + # performance of LVM commands. This daemon should never be used when + # volume groups exist that are being managed by the cluster. The lvmetad + # daemon introduces a response lag, where certain LVM commands look like + # they have completed (like vg activation) when in fact the command + # is still in progress by the lvmetad. This can cause reliability issues + # when managing volume groups in the cluster. For Example, if you have a + # volume group that is a dependency for another application, it is possible + # the cluster will think the volume group is activated and attempt to start + # the application before volume group is really accesible... lvmetad is bad. + ## + lvm dumpconfig global/use_lvmetad | grep 'use_lvmetad.*=.*1' > /dev/null 2>&1 + if [ $? -eq 0 ]; then + # for now warn users that lvmetad is enabled and that they should disable it. In the + # future we may want to consider refusing to start, or killing the lvmetad daemon. + ocf_log warn "Disable lvmetad in lvm.conf. lvmetad should never be enabled in a clustered environment. Set use_lvmetad=0 and kill the lvmetad process" + fi + + ## # Off-the-shelf tests... ## VGOUT=`vgck ${VOLUME} 2>&1` -- 1.8.4.2