Like a majority of Magento ecommerce users, I call realtime API quotes from FedEx/UPS/USPS to get the shipping rates. The majority of the time, everything works okay. However, on occasions the API goes down (scheduled maintenance or randomly).
Scheduled maintenance, the administrator can go ahead and set a flat rate or table rate ahead of time. However when it randomly goes down, this can cause a massive headache. An example of this, is when Fedex went down for 57 minutes on Black Friday (Source). This affected approximately 200 customers/orders.
I am thinking of either finding a extension or writing my own that calls one API (lets say FedEx), if Fedex doesn't respond within 3 seconds, it will attempt to call the API of UPS. Of course there will be mapping involved (Fedex Ground = UPS Ground and so on) and I know the quotes price won't be exact (FedEx might be $6.75 and UPS might be $7.35), however I am attempting to give the customer a shipping quote without them noticing a problem or a problem that prevents them to checkout.
My question is, how do other Magento sites prepare for this? Do you have failsafes? Are the failsafes done manually or programmatically?
Best Answer
The downtime of live carriers tends to be extremely rare, some are obviously worse than others, but up until recently UPS, FedEx were very stable.
There have been a few issues with FedEx recently, probably to do with Dimensional Changes going in, we have raised bugs/problems with them, and I know we have had live site outages. But in general it 'shouldn't happen'.
Saying this we have worked with customers in putting in backup carriers (it's more of a problem with Freight), and have solutions, but I can't discuss here as will get kicked off. What I can say is that there are solns out there.