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The license server is very fragile. There are many failure modes, and most vendors have not upgraded to more recent flexlm versions that are more reliable, nor to support alternative license servers when one fails or needs to be restarted due to upgrades/patching/failure. Also serving a license across a VPN may be a license violation (e.g. if the licenses is limited to a site). For more on this see VPN and license server. At the moment it appears to work, however there are no guarantees.
Can I access Confluence?
You should be able to access Confluence. If not please report this with details as a problem to net-admin.
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