Hi,

We ran into a problem if galaxy is running behind multiple reverse proxies. Galaxy assumes that the X-Forwarded-Host header only contains a single host to which it redirects, but apache will append comma-separated components to it if it already exists, which is the case of multiple reverse proxies. The result is that galaxy sometimes (i.e. sometimes after user login, depending on browser specifics, and when installing toolshed tools) tries to redirect the browser to "hostname, hostname". Apache docs