You say it complained that you had to setup the tracking server and SSL tracking server. Typically, these need to be setup on initial implementation. You shouldn't need to set these up with each additional tracking server.
With that said, the settings for tracking server and SSL tracking server in DTM are setup within your Analytics tool under the general section.
Depending on if your using first vs third party cookies, the s.trackingServerSercure variable may or may not need to be set.
If you tracking server is first-party (something like metrics.yourdomain.com) then you'll likely need to set both tracking server and tracking server secure. If you are using third-party cookies (something like companyname.omtrdc.net), you won't need to set the tracking server secure variable.
Please let me know if you have additional questions.