Replace host with getent function

SiteTests/FroNtier/tests/CE-cms-squid

@@ -2,7 +2,7 @@
 
 shopt -s expand_aliases
 
-SCRIPT_REVISION="2020-02-21, Dave Dykstra and Edita Kizinevic"
+SCRIPT_REVISION="2020-02-24, Dave Dykstra and Edita Kizinevic"
 
 # Script does not use backupproxyurl if it is SAM test, but script uses backupproxyurl if it is pilot
 includebackups=false
@@ -148,7 +148,7 @@ check_proxies() {
                 IP_addresses=`getent ahostsv4 $hostname | awk '/STREAM/{print $1}'`
                 if [ -z "$IP_addresses" ]; then
                     IP_addresses=$hostname
-                elif host $hostname | grep -q "has IPv6 address"; then
+                elif getent ahostsv6 $hostname | awk '/STREAM/{print $1}' | grep -qv ^::ffff:; then
                     IP_addresses="$IP_addresses $hostname"
                 fi
                 for IP_address in $IP_addresses; do