6.5.1

Table Of Contents
As you open ports on the firewall, consider that unrestricted access to services running on an ESXi host
can expose a host to outside attacks and unauthorized access. Reduce the risk by configuring the ESXi
firewall to allow access only from authorized networks.
Note The firewall also allows Internet Control Message Protocol (ICMP) pings and communication with
DHCP and DNS (UDP only) clients.
You can manage ESXi firewall ports as follows:
n
Use the security profile for each host in the vSphere Web Client. See Manage ESXi Firewall Settings
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Use ESXCLI commands from the command line or in scripts. See ESXi ESXCLI Firewall Commands.
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Use a custom VIB if the port you want to open is not included in the security profile.
You create custom VIBs with the vibauthor tool available from VMware Labs. To install the custom
VIB, you have to change the acceptance level of the ESXi host to CommunitySupported. See
VMware Knowledge Base Article 2007381.
Note If you engage VMware Technical Support to investigate a problem on an ESXi host with a
CommunitySupported VIB installed, VMware Support might request that this CommunitySupported
VIB be uninstalled as a troubleshooting step to determine if that VIB is related to the problem being
investigated.
ESXi Firewall Concepts (http://link.brightcove.com/services/player/bcpid2296383276001?
bctid=ref:video_esxi_firewall_concepts)
The behavior of the NFS Client rule set (nfsClient) is different from other rule sets. When the NFS
Client rule set is enabled, all outbound TCP ports are open for the destination hosts in the list of allowed
IP addresses. See NFS Client Firewall Behavior for more information.
Manage ESXi Firewall Settings
You can configure incoming and outgoing firewall connections for a service or a management agent from
the vSphere Web Client or at the command line.
Note If different services have overlapping port rules, enabling one service might implicitly enable other
services. You can specify which IP addresses are allowed to access each service on the host to avoid this
problem.
Procedure
1 Browse to the host in the vSphere Web Client inventory.
2 Click Configure.
3 Under System, click Security Profile.
The vSphere Web Client displays a list of active incoming and outgoing connections with the
corresponding firewall ports.
vSphere Security
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