Database server build not working on Ubuntu Server 15.04

[n8gard]

My chef/knife run completes successfully. The server does not start (log output below). Also, when I ssh into my newly created system and 'sudo su - postgres' it seems that I am now the postgres user, but I'm not.

whoami   #=> postgres
id -u        #=> returns uid for user: uuid
id -g        #=> returns gid for group: ssh

The server does not start. Contents of /var/log/postgresql/*.log:

2015-08-12 12:10:51 GMT LOG:  database system was shut down at 2015-08-12 12:10:46 GMT
2015-08-12 12:10:51 GMT LOG:  MultiXact member wraparound protections are now enabled
2015-08-12 12:10:51 GMT LOG:  database system is ready to accept connections
2015-08-12 12:10:51 GMT LOG:  autovacuum launcher started
2015-08-12 12:10:51 GMT LOG:  incomplete startup packet
2015-08-12 12:11:21 GMT LOG:  received fast shutdown request
2015-08-12 12:11:21 GMT LOG:  aborting any active transactions
2015-08-12 12:11:21 GMT LOG:  autovacuum launcher shutting down
2015-08-12 12:11:21 GMT LOG:  shutting down
2015-08-12 12:11:21 GMT LOG:  database system is shut down
2015-08-12 12:11:22 GMT FATAL:  could not access private key file "/etc/ssl/private/ssl-cert-snakeoil.key": Permission denied

Some investigation into the referenced key:

postgres@cb-dbtest01:~$ ls -la /etc/ssl/private/ssl-cert-snakeoil.key
-rw-r----- 1 root ssl-cert 1704 Aug 12 08:10 /etc/ssl/private/ssl-cert-snakeoil.key
postgres@cb-dbtest01:~$ cat /etc/group | grep ssl
ssl-cert:x:120:postgres

My recipe/attributes is basically a copy-n-paste from the README... I don't think I'm committing any unnatural acts here. Thoughts?

[n8gard]

UPDATE: I created an identical VM template based off Ubuntu Server 14.04.2 LTS and ran the same recipe and PostgreSQL installed and started just fine. Suspect this is, indeed, a Server 15.04 problem.

[n8gard]

Log output from another run (cat /var/log/postgresql/*.log)

2015-08-13 17:27:56 GMT LOG:  could not bind IPv6 socket: Cannot assign requested address
2015-08-13 17:27:56 GMT HINT:  Is another postmaster already running on port 5432? If not, wait a few seconds and retry.
2015-08-13 17:27:56 GMT LOG:  database system was shut down at 2015-08-13 17:27:52 GMT
2015-08-13 17:27:56 GMT LOG:  MultiXact member wraparound protections are now enabled
2015-08-13 17:27:56 GMT LOG:  database system is ready to accept connections
2015-08-13 17:27:56 GMT LOG:  autovacuum launcher started
2015-08-13 17:27:57 GMT LOG:  incomplete startup packet
2015-08-13 17:28:03 GMT LOG:  received fast shutdown request
2015-08-13 17:28:03 GMT LOG:  aborting any active transactions
2015-08-13 17:28:03 GMT LOG:  autovacuum launcher shutting down
2015-08-13 17:28:03 GMT LOG:  shutting down
2015-08-13 17:28:03 GMT LOG:  database system is shut down
2015-08-13 17:28:04 GMT FATAL:  could not access private key file "/etc/ssl/private/ssl-cert-snakeoil.key": Permission denied