This is a VICE news clip of a Ukrainian military AN-26 transport shot down a few days before MH-17. The AN-26 was flying at about 6,500m, or roughly 3,000m below MH-17. Reports say that it was not a shoulder-fired missile which shot it down, but a heavier surface-to-air weapon type. You can see the wreckage clearly in the video, but bear in mind that the AN-26 is a lot smaller than the MH-17 which is a Boeing 777-300, so there are less intact components.
Unsurprisingly, there were no consipracy theories regarding this crash, no 'US satellite photos' of the launch and no 'it was a Jet which machine-gunned it down'. Unless the Ukrainian military is incompetent enough to shoot down its own transport plane (even though the rebels have no airplanes, so why would they try to shoot anything down), then the only reasonable conclusion you can make is that the rebels possess some capability to shoot down aircraft at a great height.
The myth that an SU-25 shot down MH-17 has also been largely debunked - the service ceiling of the aircraft, detailed on the Sukhoi website itself, is 7,000m. It is not technically possible for any plane to somehow use its thrust momentum to reach up another 3,000m to the height MH-17 was flying at, something which the Pro-Russian crowd likes to deny. In fact, the SU-25's Wikipedia page has been vandalised several times by users from Russian IP addresses to magically add another 3,000m to the service ceiling of the SU-25.
EDIT: I asked this question on aviation.stackexchange just for you: https://aviation.stackexchange.com/questions/8344/can-an-aircraft-go-higher-than-its-service-ceiling/8347