There are currently no Network Block Device nodes connected to any server. As such, you can't disconnect any of them.
Akka tura ulac ula d yiwet n tkerrist n yibenk n usewḥel n uzeṭṭa yeqqnen ɣer uqeddac. Amek akka llan akka, ur tezmireḍ ara ad d-tesnesreḍ ula d yiwen seg-sen.