Q: how do you know if hard drive is bad

Try resetting the NVRAM. Its contents store boot disk info and may have been corrupt:

How to Reset NVRAM on your Mac - Apple Support

If that doesn't help look at the article on http://scsc-online.com in their how to section about hard drive problems and see if that helps. They also have a drive testing tool named Scannerz that's pretty good but the drive must first be mountable or at least partially working for it to test the drive.

I've seen many cases where the NVRAM reset does the trick.

What you are saying is ,when you use Command R, instead of a recovery screen it tries to get an internet connection. Right?  OK. What year and model Macbook Pro do you have and what operating system is it running.  https://support.apple.com/en-us/HT201314  He is a list of Mac's that can use internet recovery.   https://support.apple.com/en-us/HT202313 If you can use internet recovery from the spinning globe,. You need an active WIFI connection.

clowers43 wrote:

 

its not the hard drive i just took it out and pluged it up to my mac pro and i see everything on the drive..

Have you connected the HDD externally to your MBP  via USB and see if it will boot the MBP?i

Ciao.

While plugged into the Mac Pro, did you try running utilities through the Mac Pro to check that drive or repair. Also repairing permissions. I Know that just before you get to the globe it should have asked for your wifi settings. If these are not interred right  it will not connect. You could have a bad hard drive cable. but you would need to take OGELTHORPE'S  advise and using an external drive enclosure or cables,and try booting from it. http://osxdaily.com/2014/12/14/reinstall-os-x-mac-internet-recovery/

It could still be the hard drive if it has damage to the files used to boot the system. The boot sequence is:

1. Memory check and memory allocation
2. Device initialization
3. NVRAM validation
4. Self diagnostic check
5. Assuming NVRAM's auto-boot setting is true, it would start hunting a boot device or pay attention to keyboard re-directs
6. If a boot device is found it will start loading the OS, if it isn't the blinking folder is shown
7. The system normally boots

Personally it sounds to me like he's failing at step 4. It may be possible to catch the error by pressing and holding the command-v key combination during boot as that will boot in verbose mode instead of the normal mode with white screen, apple logo, etc. etc. In verbose mode (console mode) the system may stop and report the failure. There's no guarantee of that depending on the nature of the failure.

Since the system is a 2011 system I would assume he could attempt to boot it using the original install media, assuming he could get that far, and maybe use AHT with it. One correction to a previous post by Mr Williams was that Scannerz only works on mountable drives. Scannerz doesn't  care if a drive is mounted or not mounted since it's doing low level tests, but it needs to be operating at a system that can at least function, and it sounds like this system isn't. The same may hold true for AHT depending on the severity of the damage…i.e. if the system can't even get to the point it can load any diagnostic program, then obviously it can't run them.

clowers43 wrote:

 

its not the hard drive i just took it out and pluged it up to my mac pro and i see everything on the drive..

Click on the following 3 links:

Failing Hard Drive Sounds

How to Tell When Your Hard Drive is Going to Fail

Be prepared for hard-drive failure