Troubleshoot network monitoring
Some messages you get during Network monitoring might require actions from your side while some are just informational and do not need any reaction.
Potential network disruption during OneAgent installation on Windows
During OneAgent installation, the host might experience network communication disruption on all input and output ports. The disruption typically lasts until the end of OneAgent installation and is associated with the Npcap
installation.
Before installing OneAgent, you need uninstall any existing WinPcap
driver to allow Npcap
installation— do this on all Windows versions, except for Windows Server 2019 build 1809 without hotfix KB4571748
. For more details, see Uninstall WinPcap driver to allow Npcap installation
You do not need to take any action to restore network communication, but if you prefer to prevent disruptions, you might need to:
-
Upgrade your Windows Server version
The disruptions have been observed onWindows Server 2016
andWindows Server 2019 build 1809 without hotfix KB4571748
. Therefore, upgrading your Windows Server version should prevent such disruptions.Windows 2019 build 19042 version
is not affected. -
Disable
Microsoft Network Monitor Driver
DisablingMicrosoft Network Monitor Driver
onWindows Server 2016
andWindows Server 2019 build 1809 without hotfix KB4571748
might prevent potential disruptions.
OneAgent page allocation failure message on Linux
OneAgents operating on Linux might generate a page allocation failure message in the logs during network communication monitoring. The message format is:
Apr 29 08:07:54 (host name) kernel: oneagentnetwork: page allocation failure. order:4, mode:0xd0
This message is purely informational and does not indicate any problems with Dynatrace components, the network that you monitor, or any data loss.
Network Agent initialization failure on Windows
In some situations, Network Agent stops working and fails to restart on Windows. This may be because the pcap
driver (either Npcap
or WinPcap
) has been removed or has malfunctioned. In such cases, the Network Agent logs include the IstallInfo: appName: serviceName:no-pcap
message:
In such cases, Network Agent is repeatedly restarted by OneAgent Watchdog, but exits early without providing network metrics. In OneAgent versions earlier than 1.241, it also resulted in multiple Network Agent segmentation faults due to flawed error handling logic. Since OneAgent version 1.241, however, Network Agent initialization failure no longer results in a segmentation fault.
To verify that at least one pcap
driver is installed, execute the driverquery
command. If the driver is not installed, it will be installed automatically during the next upgrade.