INFO: Refreshing org.springframework.web.context.support.StaticWebApplicationContext@8ba8667: display name [Root WebApplicationContext]; startup date [Thu Mar 24 22:45:02 UTC 2016]; root of context hierarchy
Mar 24, 2016 10:45:02 PM org.springframework.context.support.AbstractApplicationContext obtainFreshBeanFactory
INFO: Bean factory for application context [org.springframework.web.context.support.StaticWebApplicationContext@8ba8667]: org.springframework.beans.factory.support.DefaultListableBeanFactory@11787592
Mar 24, 2016 10:45:02 PM org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
INFO: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@11787592: defining beans [filter,legacy]; root of factory hierarchy
Mar 24, 2016 10:45:02 PM jenkins.util.groovy.GroovyHookScript execute
INFO: Executing /var/jenkins_home/init.groovy.d/tcp-slave-agent-port.groovy
Mar 24, 2016 10:45:02 PM hudson.model.AsyncPeriodicWork$1 run
INFO: Started Download metadata
Mar 24, 2016 10:45:02 PM hudson.model.AsyncPeriodicWork createListener
INFO: Moved /var/jenkins_home/Download metadata.log to /var/jenkins_home/logs/tasks/Download metadata.log.1
Mar 24, 2016 10:45:02 PM hudson.model.AsyncPeriodicWork$1 run
INFO: Finished Download metadata. 6 ms
Mar 24, 2016 10:45:02 PM org.jenkinsci.main.modules.sshd.SSHD start
INFO: Started SSHD at port 50000
Mar 24, 2016 10:45:11 PM hudson.model.UpdateSite updateData
INFO: Obtained the latest update center data file for UpdateSource default
Mar 24, 2016 10:45:11 PM jenkins.InitReactorRunner$1 onAttained
INFO: Completed initialization
Mar 24, 2016 10:45:11 PM hudson.util.BootFailure publish
SEVERE: Failed to initialize Jenkins
hudson.util.HudsonFailedToLoad: java.io.FileNotFoundException: /var/jenkins_home/secrets/initialAdminPassword (No such file or directory)
at hudson.WebAppMain$3.run(WebAppMain.java:237)
Caused by: java.io.FileNotFoundException: /var/jenkins_home/secrets/initialAdminPassword (No such file or directory)
at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInputStream.<init>(FileInputStream.java:138)
at hudson.FilePath.read(FilePath.java:1751)
at hudson.FilePath.readToString(FilePath.java:1852)
at jenkins.install.SetupWizard.<init>(SetupWizard.java:110)
at jenkins.model.Jenkins.<init>(Jenkins.java:880)
at hudson.model.Hudson.<init>(Hudson.java:85)
at hudson.model.Hudson.<init>(Hudson.java:81)
at hudson.WebAppMain$3.run(WebAppMain.java:225)
Mar 24, 2016 10:45:11 PM jenkins.model.Jenkins cleanUp
INFO: Stopping Jenkins
Mar 24, 2016 10:45:11 PM jenkins.model.Jenkins _cleanUpDisconnectComputers
INFO: Starting node disconnection
Thanks for your report!
Did your Jenkins instance have any jobs defined, or was it "empty"? Did you ever view and save the global configuration form before updating to 2.0 beta?