Where is the “Fingerprint” of my Server?

There are probably more than a few times you’ve come across us talking about the fingerprint of a server. Ever wonder where to get it? Me too, so I went about and made a point of finding out.

Basically, the fingerprint is a unique grouping of characters derived from the certificate the server is using and should be unique for every certificate. PaperCut uses this certificate identifier to allow us to communicate via SSL to any device that supports it.

There’s a bunch of different methods to find this, but for ease of use, I’ll use the chrome browser to show how easy it is to find the fingerprint for your PaperCut server and copy it.
Note: Chrome calls this the “thumbprint”

We’ll demonstrate this with the self-signed certificate PaperCut installs with, some browsers may complain about this a little, but that’s generally because they want to see a certified chain back to a Trusted Root Certificate Authority (CA) and self-signed obviously doesn’t do that.

You can import your own trusted certificate into PaperCut quite easily, read more on that here - https://www.papercut.com/kb/Main/SSLWithKeystoreExplorer

Right, let’s get started then.

1. Open a secure [HTTPS] connection to your PaperCut server.
   https://[server name or IP]:9192/user
   Chrome may warn you about the site not being safe as explained above.
   1. Click advanced then proceed to site to continue.
   2. You should arrive at the screen below.
      
2. At the left of the address bar you’ll see a section that, for us, says Not secure due to it being self-signed.
   Right-click the not secure section.
   
3. Move down to the “certificates” section of the pop-up menu and select it.
   
4. A new window will appear displaying certificate information.
   1. Select the Details Tab.
   2. Scroll down to the bottom showing the “thumbprint” section.
      
5. Select the thumbprint entry and you should see a very nonsensical hex number appear as below.
   
6. Highlight this number and use Ctrl-C for Windows, or Command-C for Mac, to copy it.