vdsm creates persistant network configs that overwrite manual changes at reboot in /var/lib/vdsm/persistence/netconf You can check your other hosts for any differences there. It is recommended that networks are set up and managed through ovirt engine. On Sun, Sep 22, 2019 at 6:01 AM TomK <tomkcpr(a)mdevsys.com&gt; wrote:

Thanks All! Ok, so configured auditd to watch /etc/resolv.conf and that pointed out the problem. A host that was reverting my changes had these /etc/resolv.conf* files: [root@mdskvm-p01 etc]# grep -EiR "# Generated by NetworkManager" * grep: extlinux.conf: No such file or directory resolv.conf:# Generated by NetworkManager resolv.conf.save:# Generated by NetworkManager # <<<<<<<<<<<<<<< [root@mdskvm-p01 etc]# [root@mdskvm-p01 etc]# grep -Ei search resolv.conf resolv.conf.save resolv.conf:search mds.xyz nix.mds.xyz mws.mds.xyz resolv.conf.save:search mds.xyz [root@mdskvm-p01 etc]# and a host where changes to /etc/resolv.conf were not occurring, had these files (note the missing .save file): [root@mdskvm-p02 etc]# grep -EiR "# Generated by NetworkManager" * grep: extlinux.conf: No such file or directory resolv.conf:# Generated by NetworkManager resolv.conf-original:# Generated by NetworkManager [root@mdskvm-p02 etc]# The reason why /etc/resolv.conf was reverting on the first host is because there is a line in the following ifdown-post network script that overwrites /etc/resolv.conf from /etc/resolv.conf.save, if you have it: [root@mdskvm-p02 network-scripts]# vi ifdown-post . . . # Remove duplicate DNS entries and shift them, # to have always correct condition below... update_DNS_entries if ! is_false "${PEERDNS}" || is_true "${RESOLV_MODS}" && \     [ "${DEVICETYPE}" = "ppp" -o "${DEVICETYPE}" = "ippp" -o -n "${DNS1}" \     -o "${BOOTPROTO}" = "bootp" -o "${BOOTPROTO}" = "dhcp" ] ; then     if [ -f /etc/resolv.conf.save ]; then # <<<<<<<<<<<<<<<<<<<<<         change_resolv_conf /etc/resolv.conf.save         rm -f /etc/resolv.conf.save # <<<<<<<<<<<<<<<<<<<<<     fi     if [ "${DEVICETYPE}" = "ppp" -o "${DEVICETYPE}" = "ippp" ]; then         if [ -f /etc/ppp/peers/$DEVICE ] ; then             rm -f /etc/ppp/peers/$DEVICE         fi     fi fi . . . . And the function change_resolv_conf() effectively copies the contents of /etc/resolv.conf.save over /etc/resolv.conf thereby overwriting anything in it, if it exists (See # <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< markers below ): [root@mdskvm-p02 network-scripts]# vi network-functions # Invoke this when /etc/resolv.conf has changed: change_resolv_conf () { s=$(/bin/grep '^[\ \ ]*option' /etc/resolv.conf 2>/dev/null) if [ $# -gt 1 ]; then if [ "x$s" != "x" ]; then s="$s"$'\n' fi n_args=$# while [ $n_args -gt 0 ]; do case "$s" in *$1*) shift n_args=$(($n_args-1)) continue ;; esac s="$s$1" shift if [ $# -gt 0 ]; then s="$s"$'\n' fi n_args=$(($n_args-1)) done elif [ $# -eq 1 ]; then if [ "x$s" != "x" ]; then s="$s"$'\n'$(/bin/grep -vF "$s" $1) else # <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< s=$(cat $1) fi # <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< fi (echo "$s" > /etc/resolv.conf) >/dev/null 2>&1; # <<<<<<<<<<<<<<<<< r=$? if [ $r -eq 0 ]; then [ -x /sbin/restorecon ] && /sbin/restorecon /etc/resolv.conf /usr/bin/logger -p local7.notice -t "NET" -i "$0 : updated /etc/resolv.conf" [ -e /var/run/nscd/socket ] && /usr/sbin/nscd -i hosts # invalidate cache fi return $r } So you have to modify both files in order to persist the changes or simply remove the /etc/resolv.conf.save file..... Appears when some older interface parameters were used before I installed oVirt here, they triggered creation of the .save file. Because it exists, it's simply used by default. Hence why changes directly to /etc/resolv.conf persisted on the second host: it didn't have a /etc/resolv.conf.save file. Cheers, TK More notes and configuring auditd to watch changes to /etc/resolv.conf: https://tinyurl.com/y68dgecx On 9/22/2019 11:08 AM, Bell Levin wrote: -- Thx, TK.