when transitioning to Debian Jessie, the version of Squid jumped from 3.1.6 to 3.4.8. The squid.conf syntax is still the same as for Squid 3.1.6. The new Squid proxy will not start with the squid.conf generated by the script /opt/vyatta/sbin/vyatta-update-webproxy.pl and is now dysfunctional.
squid3 -- 3.1.6-1.2+squeeze5
squid3 -- 3.4.8-6+deb8u2