Summary

When the user is trying to integrate Atlassian applications such as Jira and confluence with Bitbucket, the connection gets failed with the below error in the logs.

"GET /system/startup HTTP/1.1" c.a.s.internal.nav.NavBuilderImpl Failed to construct a URI for the NavBuilder from the current requests. Defaulting to application properties.
java.net.URISyntaxException: Malformed IPv6 address at index 8: http://[xx.xx.xx.xx:7990]

Environment

Bitbucket version 5.16.x +

Diagnosis

Check the $BITBUCKET_HOME/shared/bitbucket.properties on your Bitbucket server to see a line similar to the below in the file. 

server.proxy-name=xx.xx.xx.xx:xxxx

The port number also will be mentioned in the server.proxy-name along with the IP or address.

Cause

Bitbucket constructs URI for proxy server from the server.proxy-name, server.proxy-port settings in bitbucket.properties file. If a proxy port is not set, but a name is, the connector's port will be used as the default.

When bitbucket tries to construct a URI with server.proxy-name setting from bitbucket.properties file, it recognizes proxy IP address as IPv6 address due to the presense of colon <IP>:<port> specified in server.proxy-name, errors out with exception Malformed IPv6 address at index 8: as it(xx.xx.xx.xx:xxxx) isn't valid IPv6.

Solution

Update server proxy-name setting in bitbucket.properties file, omitting port as port value is taken from server.proxy-port setting. 

server.proxy-name=xx.xx.xx.xx

If you are still facing the error after implementing this fix, please do get in touch with Atlassian support.