Original Description

When sharding a collection with a hashed shard key, and specifying numInitialChunks, some of these initial chunks are unable to be moved immediately afterwards.

jstests are attached.

In 2.4.9, the characterisation is:

• Only chunks on the last shard are affected.
• All but the final chunk are affected.
• Before a successful chunk move, attempting to move problem chunks gives errors such as:

  {
          "cause" : {
                  "errmsg" : "exception: ranges differ, requested: { x: 0 } -> { x: 1152921504606846974 } existing: { x: 0 } -> { x: 8070450532247928818 }",
                  "code" : 13587,
                  "ok" : 0
          },
          "ok" : 0,
          "errmsg" : "move failed"
  }
  {
          "cause" : {
                  "errmsg" : "exception: ranges differ, requested: { x: 1152921504606846974 } -> { x: 2305843009213693948 } existing: { x: 1152921504606846974 } -> { x: MaxKey }",
                  "code" : 13587,
                  "ok" : 0
          },
          "ok" : 0,
          "errmsg" : "move failed"
  }
  {
          "cause" : {
                  "errmsg" : "exception: ranges differ, requested: { x: 2305843009213693948 } -> { x: 3458764513820540922 } existing: { x: 2305843009213693948 } -> { x: MaxKey }",
                  "code" : 13587,
                  "ok" : 0
          },
          "ok" : 0,
          "errmsg" : "move failed"
  }
  ...
  

• After a successful chunk move, attempting to move a problem chunk gives a different error:

  { "ok" : 0, "errmsg" : "no chunk found with those upper and lower bounds" }
  

In 2.5.1+, the characterisation is:

• All shards are affected.
• All chunks are affected.
• Attempting to move a chunk gives errors such as:

  {
          "cause" : {
                  "errmsg" : "exception: cannot remove chunk [{ x: 0 }, { x: 1152921504606846974 }), this shard does not contain the chunk and it overlaps [{ x: 0 }, { x: 8070450532247928818 })",
                  "code" : 16855,
                  "ok" : 0
          },
          "ok" : 0,
          "errmsg" : "move failed"
  }
  {
          "cause" : {
                  "errmsg" : "exception: cannot remove chunk [{ x: 1152921504606846974 }, { x: 2305843009213693948 }), this shard does not contain the chunk and it overlaps [{ x: 0 }, { x: 8070450532247928818 }), [{ x: 1152921504606846974 }, { x: MaxKey })",
                  "code" : 16855,
                  "ok" : 0
          },
          "ok" : 0,
          "errmsg" : "move failed"
  }
  {
          "cause" : {
                  "errmsg" : "exception: cannot remove chunk [{ x: 2305843009213693948 }, { x: 3458764513820540922 }), this shard does not contain the chunk and it overlaps [{ x: 1152921504606846974 }, { x: MaxKey }), [{ x: 2305843009213693948 }, { x: MaxKey })",
                  "code" : 16855,
                  "ok" : 0
          },
          "ok" : 0,
          "errmsg" : "move failed"
  }
  ...
  

The chunks look fine in config.chunks. Restarting the affected shard server between shardCollection and moveChunk allows the chunks to be moved sucessfully, so this is likely to be a bug in ChunkManager that causes it to get confused about chunk bounds. Specifically, it looks like the upper bound is not being set properly.