stdin: Not a typewriter
mount: mounting /cow on /root failed: Invalid argument
Generating locales...
  en_US.UTF-8... up-to-date
Generation complete.
pwconv: failed to change the mode of /etc/passwd- to 0600
Using CD-ROM mount point /cdrom/
Identifying... [622ba5a213dd43b9bd3724063dee0336-2]
Scanning disc for index files...
Found 4 package indexes, 0 source indexes, 0 translation indexes and 1 signatures
Found label 'Lubuntu 15.04 _Vivid Vervet_ - Alpha amd64 (20141229)'
This disc is called: 
'Lubuntu 15.04 _Vivid Vervet_ - Alpha amd64 (20141229)'
Copying package lists...gpgv: Signature made Mon Dec 29 17:21:10 2014 UTC using DSA key ID FBB75451
gpgv: Good signature from "Ubuntu CD Image Automatic Signing Key <cdimage@ubuntu.com>"

Reading Package Indexes... 0%

Reading Package Indexes... Done
Writing new source list
Source list entries for this disc are:
deb cdrom:[Lubuntu 15.04 _Vivid Vervet_ - Alpha amd64 (20141229)]/ vivid main multiverse restricted universe
Repeat this process for the rest of the CDs in your set.
Use of uninitialized value $name in concatenation (.) or string at /usr/share/perl5/Debconf/Format/822.pm line 80.