general FTS3 setup instruction https://svnweb.cern.ch/trac/fts3/wiki/AdminGuide (tested OS Scientific Linux release 6.2 (Carbon))

Followed Duncan's guidelines (knowledge base)

• fix /etc/gai.con on SL6
• change in /etc/fts3/fts3config "IP=::"
• set in /etc/gfal2.d/gsiftp_plugin.conf "IPV6=true"