Risk is the factor you are wanting to reduce (Score 1)

What I'd suggest is something quiet alien to the tekhead. Get management on your side. Explain the issues talk about the problems. Give them easy to read bullet points. Management will then ask you "Well what do you suggest?" Well you know a lab that effectively mirrors the live environment is about as likely as rocking horse poo but ask about it anyway. If you have concerns they won't fork out the money for it then it's most likely a case that they won't but ask for it and make sure they understand and you discuss it... Assuming you didn't get a lab then talk about the change. Talk them over the mitigation you want to plan in, talk about the rollback, get them on board. Then hit them with a compromise. You know the network better than anyone; work out what equipment you do need to replicate the vast majority of the network. If 90% of your network is based upon say 3 standard models of switches/routers ask for a lab of them. Discuss that you can reduce the risk. Risk is factor you are looking at trying to reduce. You should be able to speak to you management saying. Option 1 cost $50000 99% of network tested Option 2 cost $10000 95% of the network tested Option 3 cost $5000 90% of the network tested The important thing is by getting them in on the dialog and the issue you face the risk assessment and responsibility is being shared between you and management. If things still go south you have some defence against people yelling at you, in fact management will understand the lengths you have gone to to reduce the risk & they will understand that you cannot promise 0% risk on the budget they want and they will have agreed to this...