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One propertiers of VMware (standard) virtual switches was the number of ports per switch. A parameter (120 was the default in ESXi 5.x) that define how many virtual NIC and/or vmkernel interfaces you can connect to the virtual switch portgroups.

This parameter was static and any changes require a host reboot. But starting with vSphere 5.5 (see KB 2064511) this parameter has become “elastic”.

To ensure efficient use of resources on hosts running ESXi 5.5, the ports of virtual switches are dynamically scaled up and down. A switch on such a host can expand up to the maximum number of ports supported on the host. The port limit is determined based on the maximum number of virtual machines that the host can handle. It uses only the elastic option and the ports are dynamically increased or reduced according to need. By functionality, it is similar to the auto-expand feature available in dvSwitch starting with vSphere 5.0.

The old vSphere Client report still a static parameters also on ESXi 6.0 (a good reason to don’t use this client at all):

But if you are using other tools you can see the real configuration, both with the vSphere Web Client or the host HTML5 GUI (for ESXi 6.x):


The CLI itself report a strange values, but usually high:

Andrea MauroAbout Andrea Mauro (2857 Posts)

Virtualization, Cloud and Storage Architect. Tech Field delegate. VMUG IT Co-Founder and board member. VMware VMTN Moderator and vExpert 2010-18. Dell TechCenter Rockstar 2014-15. Microsoft MVP 2014-16. Veeam Vanguard 2015-18. Nutanix NTC 2014-18. PernixPro 2014-16. Several certifications including: VCDX-DCV, VCP-DCV/DT/Cloud, VCAP-DCA/DCD/CIA/CID/DTA/DTD, MCSA, MCSE, MCITP, CCA, NPP.


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