vMotion fails to move VMs to other hosts

Products

• VMware vCenter Server

Issue/Introduction

VMs fails to vMotion to other hosts with the error:
A general system error occurred: Launch failure Transport (VMDB) error -45: Failed to connect to peer process. ThrowableProxy.cause Transport (VMDB) error -45: Failed to connect to peer process

In vobd logs, the below snippet is found.

[vob.visorfs.ramdisk.full] Cannot extend visorfs file /tmp/auto-backup.xxxxxxxxx/local.tgz.ve because its ramdisk (tmp) is full.

Environment

VMware vCenter Server 7.x

Cause

Ramdisk is full on the directory /tmp/

Resolution

• Check the /tmp directory for any file or files filling up the directory by running the command: ls -l /tmp
• Remove or move the file filling up the /tmp directory. 
• If removing/moving the file/files fails to fix the issue, then plan a downtime and reboot the ESXi host.