It sounds like it may be a port issue. What you can do is run this command repeatedly
netstat -ano | find /i "IP ADDRESS"
on the OME box while you try to run the update. When it brings back return information verify the port, and also that it shows ESTABLISHED to the side. If not the port may not be open. Use listed port and verify it is open.
Let me know what you see.
Dell | Social Outreach Services - Enterprise
Get Support on Twitter @DellCaresPro
Download the Dell Quick Resource Locator app today to access PowerEdge support content on your mobile device! (iOS, Android, Windows)