Do we know what the warrant stated? If it authorized them to take the rack containing the server they were after, then this is legal, if unfortunate.
If the police have a warrant for my apartment, and you happen to leave your backpack and server, your stuff will most likely be confiscated, along with mine, if it interests the police.
If the police have a warrant for my apartment, and you happen to leave your backpack and server, your stuff will most likely be confiscated, along with mine, if it interests the police.