Cisco Cisco Expressway Maintenance Manual
Field
Description
Usage tips
Retry interval
The interval in seconds with which a failed attempt to
establish a connection to the traversal server should be
retried.
establish a connection to the traversal server should be
retried.
Location
section:
Peer 1 to Peer 6
address
address
The IP address or FQDN of the traversal server.
If the traversal server is an Expressway-E cluster, this
should include all of its peers.
should include all of its peers.
for
more information.
Configuring traversal server zones
An Expressway-E can act as a traversal server, providing firewall traversal on behalf of traversal clients (an
Expressway-C).
Expressway-C).
To act as a traversal server, the Expressway-E must have a special type of two-way relationship with each
traversal client. To create this connection, you create a traversal server zone on your local Expressway-E
and configure it with the details of the corresponding zone on the traversal client. (The client must also be
configured with details of the Expressway-E.)
traversal client. To create this connection, you create a traversal server zone on your local Expressway-E
and configure it with the details of the corresponding zone on the traversal client. (The client must also be
configured with details of the Expressway-E.)
After you have neighbored with the traversal client you can:
n
provide firewall traversal services to the traversal client
n
query the traversal client about its endpoints
n
apply transforms to any queries before they are sent to the traversal client
n
control the bandwidth used for calls between your local Expressway and the traversal client
Note: traversal client-server zone relationships must be two-way. For firewall traversal to work, the traversal
server and the traversal client must each be configured with the other’s details (see
server and the traversal client must each be configured with the other’s details (see
firewall and query each other. For full details on how traversal client zones and traversal server zones work
together to achieve firewall traversal, see
together to achieve firewall traversal, see
must be configured for traversal zones to work.
The configurable options for a traversal server zone are:
Field
Description
Usage tips
Configuration
section:
Name
The name acts as a unique identifier, allowing you to
distinguish between zones of the same type.
distinguish between zones of the same type.
Type
The nature of the specified zone, in relation to the
local Expressway. Select Traversal server.
local Expressway. Select Traversal server.
After a zone has been created, the
Type cannot be changed.
Type cannot be changed.
Hop count
The hop count is the number of times a request will
be forwarded to a neighbor gatekeeper or proxy (see
the
be forwarded to a neighbor gatekeeper or proxy (see
the
section for more information). This
field specifies the hop count to use when sending a
search request to this particular zone.
search request to this particular zone.
If the search request was received
from another zone and already has a
hop count assigned, the lower of the
two values is used.
from another zone and already has a
hop count assigned, the lower of the
two values is used.
Cisco Expressway Administrator Guide (X8.5.1)
Page 123 of 399
Zones and neighbors
Configuring zones