On VMware vShield Zones 4.0 limitations

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Dave Convery, VMware vExpert and Virtualization Architect at Anexinet, published a short but very interesting report on current limitations of vShield Zones, the firewall that VMware acquired from Blue Lane Technologies in October 2008 and that offers for free as part of vSphere 4.0 Advanced, Enterprise and Enterprise Plus editions.

He specifically mentions three shortcomings related to:

  • Networking
    …there is an unprotected Port Group (ORIGINAL Network). This needs to be added to the vSwitch AFTER the vShield Agent is installed. If the ORIGINAL Network is already a part of the vSwitch, it will need to be removed BEFORE installing the vShield Agent. In order to avoid an outage, you will need to disable DRS and manually vMotion all VMs off of the ESX/ESXi host before installing the vShield Agent and modifying the port groups.
  • DRS/HA
    …with HA disabled for the vShield Agent, there is no facility for automatic startup. There is an automatic startup setting in the startup/shutdown section of the configuration settings. First, this is an all-or-nothing setting. Second…if a host fails, HA will restart all protected VMs on different hosts. If the host comes back on line, you risk having DRS migrate protected VMs back to that host. This will cause those VMs to become disconnected because the vShield Agent will not automatically start. If a host fails, hope that it fails good enough so it won’t restart.
  • Maintenance Mode
    …you cannot power the vShield Agent off because the protected VMs would become disconnected. You cannot migrate it to a different host because it would cause a serious conflict and cause protected VMs to become disconnected. The only thing you can do is place the host in Maintenance Mode, then MANUALLY (*GASP*) migrate all of the protected VMs and then power the vShield Agent off. So much for automated patch management

Convery closes his (very welcome) report by saying that vShield Zones is a 1.x product, implying that some of the issues above are expected in a first generation product. Unfortunately it doesn’t seem the case: well before VMware acquired Blue Lane Technologies, vShield (formerly VirtualShield) already was at its 4th generation (Sep 2007). VMware acquired the startup one year later (so it’s safe to assume that Blue Lane made significant progresses in that timeframe) and had from October 2008 to May 2009 to deliver a more integrated platform.