Cisco Cisco Expressway Maintenance Manual
In such a deployment, traversal clients should be configured to use the internally-facing IP address of the
Expressway-E.
Expressway-E.
To enable the use of a static NAT:
1. Ensure that the Advanced Networking option key is installed.
2. For the externally-facing LAN port:
a. In the IPv4 address field, enter the Expressway-E's private IP address.
b. Set IPv4 static NAT mode to On.
c. In the IPv4 static NAT address field, enter the Expressway-E's public IP address - this is the IP
b. Set IPv4 static NAT mode to On.
c. In the IPv4 static NAT address field, enter the Expressway-E's public IP address - this is the IP
address of the outside of the NAT.
Static NAT restrictions when using SIP media encryption
You should not configure an Expressway for SIP media encryption if that same Expressway is also
configured for static NAT. If you do so, the private IP address will be sent in the SDP rather than the static
NAT address and this will cause calls to fail.
configured for static NAT. If you do so, the private IP address will be sent in the SDP rather than the static
NAT address and this will cause calls to fail.
Note that the recommended configuration for Expressway-C with Expressway-E deployments is to:
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configure the same media encryption policy setting on the traversal client zone on Expressway-C, the
traversal server zone on Expressway-E, and every zone on Expressway-E
traversal server zone on Expressway-E, and every zone on Expressway-E
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use static NAT on the Expressway-E only
With this configuration the encryption B2BUA will be enabled on the Expressway-C only.
Configuring Ethernet settings
The
Ethernet
page (
System > Ethernet
) is used to configure the speed of the connection between the
Expressway and the Ethernet switch to which it is connected. The speed must be set to the same value on
both systems. If you have the Advanced Networking option enabled, you can configure the Ethernet speed
separately for each LAN port.
both systems. If you have the Advanced Networking option enabled, you can configure the Ethernet speed
separately for each LAN port.
The default is Auto, which means that the two systems will auto-negotiate the appropriate speed.
Note: we recommend that you use the default value of Auto unless the switch to which you are connecting is
unable to auto-negotiate. A mismatch in Ethernet speed settings between the Expressway and Ethernet
switch will at best result in packet loss; at worst it will make the system inaccessible for endpoints and
system administrators.
unable to auto-negotiate. A mismatch in Ethernet speed settings between the Expressway and Ethernet
switch will at best result in packet loss; at worst it will make the system inaccessible for endpoints and
system administrators.
Configuring DNS settings
The
DNS
page (
System > DNS
) is used to configure the Expressway's DNS servers and DNS settings.
Configuring the system host and domain name
The System host name defines the DNS host name that this Expressway is known by.
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It must be unique for each peer in a cluster.
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It is used to identify the Expressway on a remote log server (a default name of "TANDBERG" is used if the
System host name is not specified).
System host name is not specified).
Cisco Expressway Administrator Guide (X8.1.1)
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Network and system settings
Network settings