O365 / Exchange 2010 : Hybrid - Secure Exchange

[CapnPugwash]

Setting up O365 / Exchange 2010 hybrid. Had a few problems with our ISP who charge a fair bit to make ANY change to the firewall. We've now agreed that they will open port 25 etc. and we will have to secure Exchange at our end to prevent it being used as a Spam Relay. The reason for this is if they handled the Microsoft IP range at their end, every time it changed they would charge me again (and again!)

 

How do I go about securing Exchange?

 

I've run the Hybrid configuration wizard and it has created O365 connectors with, what I presume are the EOP IP addresses.... not sure what else I need to do & everytime I speak to the ISP they raise the PANIC LEVEL!

[psydii]

Change your ISP.

 

/stevejobs.

[CapnPugwash]

Change your ISP.

 

/stevejobs.

 

Ha! Yes. It's on the list.

[CapnPugwash]

In case anyone is following or in the same boat...

 

This has been a real pain & we've got no one to blame but ourselves (or myself, as I'm the only one involved) Problems with the ISP/Firewall should have been anticipated sooner & prepared for... it's just another over familiar case of people wanting big things and wanting them TODAY!

 

Our LEA is our broadband supplier. They lease the connection from someone else. I think the business relationship may have broken down somewhat as next year they are leasing it from another supplier so at a guess, this is adding more layers of complexity to the whole thing as my requests Ping-Pong between the two of them. This should have been a lot easier than it has been.

 

Because I have to get things sorted RIGHT NOW! I've told them to open the relevant firewall ports and tie them down to the IP's in the current MSoft list. If the list changes and we have to pay another load of ££££ to put in another firewall request, that's just the way it will have to be. I am not confident that I can secure our Exchange server in the next 24hrs, so it's the only way forward.

 

Once we have O365 working I can set up pfsense - an onsite firewall would protect Exchange (we currently don't have an on-site firewall or an Exchange Edge server)

 

MERRY XMAS!