Reachability sometimes fails, even when we do have an internet connection

iphone, objective-c

Solution

Looks like you've stripped out some basic reachability code from the Apple example code. What happens when you leave it intact and do this?

Reachability *hostReach = [[Reachability reachabilityWithHostName: @"www.apple.com"] retain];

NetworkStatus netStatus = [hostReach currentReachabilityStatus];

if (netStatus == NotReachable)
{
    NSLog(@"NotReachable");
}

if (netStatus == ReachableViaWiFi)
{
    NSLog(@"ReachableViaWiFi");
}

if (netStatus == ReachableViaWWAN)
{
    NSLog(@"ReachableViaWWAN");
}

Problem

I've searched but can't see a similar question. I've added a method to check for an internet connection per the Reachability example. It works most of the time, but when installed on the iPhone, it quite often fails even when I do have internet connectivity (only when on 3G/EDGE - WiFi is OK). Basically the code below returns NO. If I switch to another app, say Mail or Safari, and connect, then switch back to the app, then the code says the internet is reachable. Kinda seems like it needs a 'nudge'. Anyone seen this before? Any ideas? Many thanks James ``` + (BOOL) doWeHaveInternetConnection{ BOOL success; // google should always be up right?! const char *host_name = [@"google.com" cStringUsingEncoding:NSASCIIStringEncoding]; SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithName(NULL, host_name); SCNetworkReachabilityFlags flags; success = SCNetworkReachabilityGetFlags(reachability, &flags); BOOL isAvailable = success && (flags & kSCNetworkFlagsReachable) && !(flags & kSCNetworkFlagsConnectionRequired); if (isAvailable) { NSLog(@"Google is reachable: %d", flags); }else{ NSLog(@"Google is unreachable"); } return isAvailable; ``` }

Original source