Citrix NetScaler EE, Руководство по установке и настройке

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Selecting a Deployment Mode
Oct 08, 2013
The SD-WAN 4000/5000 appliance can be deployed inline or in a one-arm mode. Inline deployments do not require router
reconfiguration; one-arm modes do. SD-WAN 4000/5000 offers internal port bypassing (fail-to-wire) to allow traffic to
continue flowing in inline mode if the appliance fails.
Note: Only the one-arm WCCP mode (with a single router) is documented at this time. Inline mode is not yet documented.
Citrix recommends WCCP mode at this time.
Different SD-WAN 4000/5000 models offer different numbers of accelerated bridges. Models with multiple accelerated
bridges can accelerate multiple inline WAN links. See the specifications sheet for more details,
http://www.citrix.com/content/dam/citrix/en_us/documents/products-solutions/SD-WAN-data-sheet.pdf .
Deploying a Single SD-WAN 4000/5000 Appliance (or HA Pair)
A standalone SD-WAN 4000/5000 appliance can be deployed in either of these two recommended modes:
Inline, bridged (L2 inline). This closely resembles a standard SD-WAN inline deployment. Packets enter one bridge port and
exit the other bridge port.
One-arm, WCCP. This resembles a standard SD-WAN WCCP deployment.
Citrix also supports the following two modes (which are outside the scope of this document):
Inline, routed. The NetScaler instance uses routing rules instead of bridging rules to determine how to forward packets.
Virtual inline. This resembles WCCP, but lacks built-in health-checking.
In L2 inline mode, SD-WAN 4000/5000 is placed between your LAN and your WAN router (or other aggregation point at the
LAN-WAN boundary). In a one-arm mode, SD-WAN 4000/5000 is generally connected directly to a dedicated port on your
WAN router.
In cases where the WAN router ports are not as fast as the LAN (for example, when the WAN router has gigabit Ethernet,
but the LAN has10 gigabit Ethernet), inline mode provides better performance, because its LAN-side traffic is not limited to
the speed of the router interface. (Compression allows the LAN-side traffic to be much faster than WAN-bound traffic
under favorable conditions.)
Considerations:
The inline modes require no reconfiguration of your routers, but involves a service disruption when bringing the appliance
into service.
One-arm modes require router reconfiguration but do not require a service disruption.
Inline mode has higher performance than the other modes.
One-arm modes are limited to half the speed of the router or switch port they are attached to.
With WCCP mode, configuring the router to send only a fraction of the WAN traffic to SD-WAN 4000/5000 (as little as
the traffic from a single remote site or even a single remote IP address) makes it easy to bring up and test the
installation gradually. Inline mode requires that all WAN traffic pass through the appliance.
WCCP mode requires more configuration of the SD-WAN 4000/5000 appliance than do other modes, but is more
standardized and provides more status information on the router.
Recommendation:
The greater control provided by WCCP, and especially the ability to put the deployment into service in stages, makes
WCCP the mode of choice for larger, more complex datacenters, especially if there might be a possibility of overloading