xStack
®
DGS-3600 Series Layer 3 Managed Gigabit Ethernet Switch
RSPAN
RSPAN (Remote Switched Port Analyzer) is a feature used to monitor and analyze the traffic passing through ports. The character
‘R’ is short for ‘Remote’ which means that the mirror source ports and the destination port are not on the same Switch. So a
remote mirror session consists of at least two switches. To achieve the remote mirroring function, the mirrored traffic is tagged
with a reserved VLAN which is called an RSPAN VLAN, the RSPAN VLAN is reserved in such a way that traffic tagged with
RSPAN will be mirrored toward the associated destination port.
There are three roles for switches in RSPAN.
Source switch –
The switch which has the monitored ports or VLANs on it is the source switch. All packets on the source ports or
VLANs are copied and sent to the destination switch. When the mirrored packets are sent out from the source switch, an RSPAN
VLAN tag is added to every packet. The incoming port on the source switch for the mirrored packets is referred to as the
source
port
.
Intermediate switch
The function of the intermediate switch is to mirror traffic flowing in the RSPAN VLAN toward the
RSAPN destination. A switch can be have the role of an RSAPN VLAN intermediate switch as well as the role of source switch
for another RSPAN VLAN.
Destination Switch
The port which is directly connected to a network analyzer, other monitoring, or security device is called the
destination port
. The switch which has a destination port is called the
destination switch
. The destination switch removes the
RSPAN VLAN tags from the mirrored packets when the destination port is an untagged port in the RSPAN VLAN. If the
destination port is a tagged port, the tags will be reserved.
RSPAN State Settings
This window allows the user to enable or disable the RSPAN settings on the Switch. The purpose of the RSPAN function is to
mirror the packets to the remote switch. The packet travels from the switch where the monitored packet is received, through the
intermediate switch, then to the switch where the sniffer is attached. The first switch is also named the source switch.
To view this window, click
Administration > RSPAN > RSPAN State Settings
, as shown below:
Figure 2- 62. RSPAN State Settings window
Use the drop-down menu to enable or disable the RSPAN State on the Switch and click
Apply
to implement the changes made.
RSPAN Settings
This window allows the user to search for a previously created VLAN and to view the RSPAN settings for it.
To view this window, click
Administration > RSPAN > RSPAN Settings
, as shown below:
Figure 2- 63. RSPAN Settings window
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