Apache basic authentication issue with reverse proxy
Do you have authentication enabled on Jenkins as well? See this link: https://wiki.jenkins-ci.org/display/JENKINS/Apache+frontend+for+security for instructions on setting this up.
Particularly note the line which says that you cannot have security enabled in Jenkins and Apache simultaneously as the two will conflict, causing the infinite prompt you are seeing. Unfortunately you have to choose one or the other.
Also see this link for a more general discussion of Apache + Jenkins setup: https://wiki.jenkins-ci.org/display/JENKINS/Running+Jenkins+behind+Apache
Try this config
ProxyPass /jenkins/ http://localhost:8080/jenkins/ProxyPassReverse /jenkins/ http://localhost:8080/jenkins/ProxyRequests OffProxyPreserveHost On<Proxy http://localhost:8080/jenkins*> AllowOverride None Order allow,deny allow from all AuthName "jenkins" AuthBasicProvider file AuthType basic AuthUserFile /etc/apache2/passfile <Limit GET POST> require valid-user </Limit> Satisfy all</Proxy>