I had to go to terminal and enter mysql.server start. The mysqlbackend log indicated that it couldn't connect to the server. When I ran mysql.server start I got the message success and was able to start the backend.
Here's the log.
2014-11-18 17:06:56.313518 C [19/2579] thread_unknown mythcommandlineparser.cpp:2595 (ConfigureLogging) - mythbackend version: fixes/0.27 [v0.27.4-b305eb5b-MacPorts]
www.mythtv.org
2014-11-18 17:06:56.313549 C [19/2579] thread_unknown mythcommandlineparser.cpp:2597 (ConfigureLogging) - Qt version: compile: 4.8.6, runtime: 4.8.6
2014-11-18 17:06:56.313555 N [19/2579] thread_unknown mythcommandlineparser.cpp:2599 (ConfigureLogging) - Enabled verbose msgs: general
2014-11-18 17:06:56.313757 N [19/2579] thread_unknown logging.cpp:907 (logStart) - Setting Log Level to LOG_INFO
2014-11-18 17:06:56.336914 I [19/7939] Logger logging.cpp:308 (run) - Added logging to the console
2014-11-18 17:06:56.337450 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Interrupt: 2 handler
2014-11-18 17:06:56.337455 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Terminated: 15 handler
2014-11-18 17:06:56.337459 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Segmentation fault: 11 handler
2014-11-18 17:06:56.337462 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Abort trap: 6 handler
2014-11-18 17:06:56.337466 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Bus error: 10 handler
2014-11-18 17:06:56.337470 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Floating point exception: 8 handler
2014-11-18 17:06:56.337473 I [19/2579] thread_unknown signalhandling.cpp:194 (SetHandlerPrivate) - Setup Illegal instruction: 4 handler
2014-11-18 17:06:56.337696 N [19/2579] thread_unknown mythdirs.cpp:55 (InitializeMythDirs) - Using runtime prefix = /opt/dvr
2014-11-18 17:06:56.337704 N [19/2579] thread_unknown mythdirs.cpp:68 (InitializeMythDirs) - Using configuration directory = /opt/dvr/var/mythtvuser/.mythtv
2014-11-18 17:06:56.337769 I [19/2579] CoreContext mythcorecontext.cpp:257 (Init) - Assumed character encoding:
2014-11-18 17:06:56.337773 W [19/2579] CoreContext mythcorecontext.cpp:264 (Init) - This application expects to be running a locale that specifies a UTF-8 codeset, and many features may behave improperly with your current language settings. Please set the LC_ALL or LC_CTYPE, and LANG variable(s) in the environment in which this program is executed to include a UTF-8 codeset (such as 'en_US.UTF-8').
2014-11-18 17:06:56.339469 N [19/2579] CoreContext mythcontext.cpp:504 (LoadDatabaseSettings) - Empty LocalHostName.
2014-11-18 17:06:56.339478 I [19/2579] CoreContext mythcontext.cpp:512 (LoadDatabaseSettings) - Using localhost value of iMac
2014-11-18 17:06:56.354329 E [19/2579] CoreContext mythdbcon.cpp:216 (OpenDatabase) - Unable to connect to database!
2014-11-18 17:06:56.354358 E [19/2579] CoreContext mythdbcon.cpp:217 (OpenDatabase) - Driver error was [1/2002]:
QMYSQL: Unable to connect
Database error was:
Can't connect to local MySQL server through socket '/opt/dvr/var/run/mariadb/mysqld.sock' (2)
2014-11-18 17:06:56.354539 C [19/2579] CoreContext main.cpp:129 (main) - Failed to init MythContext.
2014-11-18 17:06:56.515260 I [19/6155] LogForward loggingserver.cpp:1373 (forwardMessage) - New Client: (#1)
2014-11-18 17:06:56.535647 I [-1/6155] loggingserver.cpp:142 (FileLogger) - Added logging to /opt/dvr/var/log/mythtv.27/mythbackend.20141118230656.19.log