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using the same IP addresses on the secondary as with the primary. The IP address
you create for you additional server network will be used as the server’s default
gateway IP. Since only the active WebMux will have this IP enabled on its interface,
you will not have a duplicate IP address between both units. If one unit goes out of
service, the IP address becomes available on the other unit and the servers can
continue to communicate to the external network uninterrupted.
Transparent Mode VLAN:
In Transparent mode, it is recommended that you assign a different VLAN ID for the
physical front and back interfaces with the -r (—router_vid) and -s (—server_vid)
flags.
For example:
nwconfig -A tm_vlan -i 192.168.14.21 -g 192.168.14.1 -r 200 -s 300
If you use the -v flag, both the physical front and back interfaces will have the
same VLAN ID. It is not recommended that you use the same VLAN ID for the
front and back interfaces in Transparent mode.
Out-of-Path Mode VLAN and Server LAN Gateway:
When creating an additional network in Out-of-Path Mode, it is important that your
farm IPs are different from the main IP address you create with the “nwconfig” tool.
This is important because the main IP address you create will be the IP address the
WebMux unit’s health checks will appear to come from. You will have problems with
Windows® servers if you use a farm IP that is the same as the main IP. This is
because Windows® utilizes the MS Loopback Adapter with the farm IP. When the
WebMux send its health check request coming from the main IP, the Windows®
machine will see that the IP address is on its Loopback Adapter and will not send
back a reply since it believes it is coming from itself. The WebMux will mark the
server dead since it will not receive a reply. To ensure that this will not occur, do not
use a farm IP that is the same as the main IP in Out-of-Path Mode.
It is important to remember that when you are running a setup involving SSL
termination that you must point your servers’ default gateway back to the WebMux.
In the original network configuration, you had an option to create a “server LAN
gateway IP.” The servers used this IP address as their default gateway IP. This IP is
a floating IP that transfers between WebMux units in a failover configuration. Only
the active WebMux will have that IP address available on its network interface to
avoid duplicate IP address issues.
Additional network configurations do not have the option to create a “server LAN
gateway IP” like the original network configuration. In this case, you will need to use
the FARM IP as your servers’ default gateway IP address. Since the FARM IPs are
only available on the active WebMux they will effectively serve as the floating server
LAN gateway IP.
Configuration Wizards
