Trying to manually relocate a shard returns the following error. We are using shadow replicas in our setup.

{
"error": "ElasticsearchIllegalArgumentException[[move_allocation] can't move [accesslogging_hawthorne-2015-09-01][1], from [Sputnik][28AZOAhAQV6ThZyCB5oP4g][halitods4.datacenter.automotive.com][inet[/10.1.68.42:9300]]{site=hawthorne, tag=shadowcopy, enable_custom_paths=true, master=false}, to [Thirty-Three][NWA5D0HIRAe-7XaHtfiq7g][halitods5.datacenter.automotive.com][inet[/10.1.68.43:9300]]{site=hawthorne, tag=shadowcopy, enable_custom_paths=true, master=false}, since its not allowed, reason: [YES(shard is not allocated to same node or host)][YES(node passes include/exclude/require filters)][YES(shard is primary)][YES(below shard recovery limit of [2])][YES(allocation disabling is ignored)][YES(allocation disabling is ignored)][YES(no allocation awareness enabled)][YES(total shard limit disabled: [-1] <= 0)][YES(target node version [1.7.1] is same or newer than source node version [1.7.1])][NO(after allocation more than allowed [85.0%] used disk on node, free: [0.9657585087747922%])][YES(no snapshots are currently running)]]",
"status": 400
}