Hi

(06:42:11) | Rust:IO> Steam authentication failed: WebException The request timed out

at System.Net.HttpWebRequest.GetRequestStream () [0x0004d] in <0079a30f96a047348857e1cecc6c638a>:0

at B.X.A (B.L , System.String& ) [0x00221] in <66e12633625c4a02a83f37a4a0c209e4>:0

Generally this means that either Steam had a hiccup, else your server cannot access Steam.