Introduction
In a well-designed network, each individual device or node is assigned a unique IP address. However, in some cases, multiple devices may share the same IP address, either due to a misconfiguration or a deliberate attempt to bypass security measures. Another type of network issue is a routing loop, which occurs when there is a circular path in the routing table. This causes packets to keep bouncing back and forth among two or more network devices, instead of being forwarded directly to their intended destination. This can result in network congestion, decreased performance, and even network downtime.
The network visualizations in Smartboard and Records highlight repeated IPs and routing loops, making it easier for you to identify and resolve these types of issues.
Visualizing Repeated IPs & Routing Loops
If the same IP is duplicated on two different nodes in the network path, then any repeat occurences of the IP (after the first) are displayed with a glyph indicator (yellow circle).
Fig 1: Yellow circle glyph indicates a repeated IP address in the network path.
Example paths with repeated IPs:
- Source -> IP1 -> IP2 -> IP2 -> Destination
(Duplicate IP - the second occurence of IP2 will be marked) - Source -> IP1 -> IP2 -> IP1 -> Destination
(Possible Routing Loop or duplicate IP - the second occurence of IP1 will be marked)
Records Page
The hop-by-hop visualization and traceroute table highlight IP addresses that have been seen more than once within a path. The indicator will be present on all repeats of a given IP, regardless of how many repeats there are.
Fig 2: Repeating IPs on Records page network path visual and traceroute table.
Smartboard
The IP Network visualization highlights IP addresses that have been seen more than once within a path. The indicator will be present on all repeats of a given IP, regardless of how many repeats there are.
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Fig 3: Repeating IPs in IP Network visual.
When there are repeated IPs in a network path, a quick-select observation filter will be available. This filter can be selected from the command bar > insight section. This will list the number of paths with repeating IPs and can be applied as a path filter.
Fig 4: Repeating IPs command bar observation.