In reality, DNS has nothing to do with PUSH. DNS resolves hostname to IP address until the TTL (Time to live) expires, when that expires, it re-query's DNS for the IP again.
I can say that in the last week, Push works on and off. For no reason. DNS set differently on Corporate Network vs. home network. I personally use OpenDNS not Google DNS.
The fact that the issue still is happening, and each user has different experence with what "fixes" it points out even more the glaring fact that there is a single common demoniator. iPhone, and None of this happened before iOS 5 was pushed.
I just keep trying to reiterate that in troubleshooting across multiple technical levels and experences, looking for the single common denominator is the best way to idenify the root cause.
Not dogging anyones assumption or analysis, as the more variables we have, with possible fixes leads us (and not apple since they do not seen to give a ****) to the real root cause.
You are right, even myself couldn't understand how DNS affected this. Anyway, I had not "sporadic" problems with push mail. It just stopped to work with my home network (from 5.1 as I can recall, it used to work when iCloud launched, so 5.0 was ok. Interestingly my sister's iPhone is still 5.0 and it stopped receiving pushed mails).
But now I can say that for 3 days ALL my mails were pushed within seconds, not even a single problem. With both our iPhones (and an iPad 3). If I go back to Google DNS push stops working again.
Some users have indicated it's a wi-fi problem and I believe they are on to something. My iPhone 4S on iOS 5.1 will not push email when connected to my home wi-fi but will push email on 3G. While it can be said the router is the problem, my third-gen iPad on iOS 5.1 pushes email fine on wi-fi.
So this problem may be something to do with iOS 5.1 and iPhones.
My push mail has been better today also.
However, I have now gotten to the point where I have had emails disapear in the past, that I have lost confidence with Apple and the iCloud system.
And because I no longer trust it because of the mails that have gone missing, I am really questioning the value of IOS given its problems.
I have used apple computers for as long as I can remember, but I have lost faith in its IOS / Cloud system.
As what is the point in using such a system when push is sporadic, but more importantly emails are going astray.
How do I know more mails are not getting through to me and are being lost or deleted?
But have started to learn my lesson in regards to the value of this now free email thing.
You get what you pay for and even less.
Maybe this has something to do with it. I mean the spordaic nature of the problem is very difficult to troubleshoot.
But it is odd that this is news:
That being said, I do not use MobileMe or iCloud, unless you count the "find the phone" functionallity. And it seemed you HAD to configure ios 5.0.1 with icloud, evern before you were given the option to turn off the parts that sync.
At any rate, it is still on again off again working.
What I thought was Push working again a couple of days ago, was to be short lived! It's back to its usual erratic self! I should know this by now as previously mentioned, has been like that for months!
Even the fetch is not working eg when I looked at mail on iPhone first thing this morning (7am) a mail sent at 00:01 and one at 06:35 both suddenly showed up in the inbox! And yes Push ON and I have fetch switched to receive every 15mins.
Just recently upgraded from 3G to 4S and migrated from MobileMe to iCloud.
Having the same problems as everyone else. Push is unreliable. My Push is on, Fetch is at 15mins, Mail Notifications is on, Cellular Data Network is on.
Spoke to Apple Guru and we temporarily fixed the problem yesterday ~ only for Mail not to work properly this morning !
So with 80,000 views and 540 replies on this thread I wonder if this worth considering going to press. I work for 'The Times' !!
General consencus is that it is a server issue. I think it goes far deeper.
Keep Calm and Carry On
MobileMe to iCloud
My Push is on, Fetch is at 15mins, Mail Notifications is on, Cellular Data Network is on.
Mostly on Wifi but have good 3G coverage
Havent had a pushed email for about a month, on my iPhone & iPad
I'm turning off push and putting it on 15 mins to try and get some emails to come through.
Hating hating hating Apple atm