"could not connect to the HTTP server server"

Hi,

Self Service will be using the same port as the clients normally use to access the JSS. If its at its default it should be 8443.

I'm not sure where the clients are when they get the error in relation to your JSS or if it is a new problem, but it sounds like the port will be getting blocked.

You can always do a quick test from the Mac client with the following command: nc -z your.jss.com 8443. You should get back something like: Connection to your.jss.com port 8443 [tcp/pcsync-https] succeeded!. If you don't, that will be the problem.

Do you use multiple distribution points? Do you have split DNS for multiple JSS webapps?

The clients are all onsite in the office. This has been an issue for the last two months and has been very intermittent. For ex, one day John will get the http error when downloading package A. Mary can download package A the same day and it succeeds. John can try again tomorrow to download the same package and it works.

We have a single distribution point. Unsure about the split dns for multiple JSS webapps. How can I check this?

It seems like this issue is pointing in the direction of a network related issue?

Sounds like you're experiencing the issue described here:
https://jamfnation.jamfsoftware.com/discussion.html?id=11138

@mm2270 Sounds similar, but I think it's a little different. Mine isn't happening all the time and is only happening to about 5-10% of our machines.

They can manually connect to the http site using the curl command or opening a web browser and entering the website.

I ended up using "force over smb/afp" to get it to sync. Not sure why http is not working for a few machines...