lucid server release 20150427 precise server release 20170502 saucy server release 20140709 trusty server release 20191107 utopic server release 20150708 vivid server release 20151219 wily server release 20160106 xenial server release 20210416 bionic server release 20210415 eoan server release 20200331 focal server release 20210415 groovy server release 20210415.1 hirsute server release 20210422