SummaryThe throughput graph on the dashboard shows strange traffic spikes above limits set in the Optimizer
OverviewWhen looking at the dashboard at a glance, there is a graph that shows the throughput over time of the inbound and outbound direction through the Exinda. This is a handy way to take a quick look at how much and what type of traffic the system is handling. In this situation, there can be times where the graph spikes beyond any set limitations in the optimizer configuration. For example, if the optimizer is set to max connections at 50Mbps, but there is the occasional spike to 60Mbps.
CauseThe number one culprit for this is Edge Cache. As of v7.0.3, edge cache does not respect QoS done by the Exinda. If an item is cached and then served from the Exinda, it can do so at LAN speeds (as opposed to going out and retrieving the information from the WAN). The interfaces graph will still show the information "going out" of the Exinda even though there is no inbound bandwidth being consumed, and the graph will erroneously show a spike corresponding to an edge cached request.
ResolutionUpgrade to ExOS 7.4, this contains the bug fix for this problem.
Additional InformationIf this problem persists when Edge Cache is turned on (or it hasn't been enabled in the first place), please inform Exinda TAC.