From c21c3b0befeb46a51b6bf3758ffa30813bea0ff0 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 9 Mar 2024 14:19:22 +0100 Subject: Adding upstream version 1.44.3. Signed-off-by: Daniel Baumann --- .../portcheck/portcheck_connection_timeouts.md | 41 ++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 health/guides/portcheck/portcheck_connection_timeouts.md (limited to 'health/guides/portcheck/portcheck_connection_timeouts.md') diff --git a/health/guides/portcheck/portcheck_connection_timeouts.md b/health/guides/portcheck/portcheck_connection_timeouts.md new file mode 100644 index 000000000..5386f1509 --- /dev/null +++ b/health/guides/portcheck/portcheck_connection_timeouts.md @@ -0,0 +1,41 @@ +### Understand the alert + +The `portcheck_connection_timeouts` alert calculates the average ratio of connection timeouts when trying to connect to a TCP endpoint over the last 5 minutes. If you receive this alert, it means that the monitored TCP endpoint is unreachable, potentially due to networking issues or an overloaded host/service. + +This alert triggers a warning state when the ratio of timeouts is between 10-40% and a critical state if the ratio is greater than 40%. + +### Troubleshoot the alert + +1. Check the network connectivity + - Use the `ping` command to check network connectivity between your system and the monitored TCP endpoint. + ``` + ping + ``` + If the connectivity is intermittent or not established, it indicates network issues. Reach out to your network administrator for assistance. + +2. Check the status of the monitored TCP service + - Identify the service running on the monitored TCP endpoint by checking the port number. + - Use the `netstat` command to check the service status: + + ``` + netstat -tnlp | grep + ``` + If the service is not running or unresponsive, restart the service or investigate further into the application logs for any issues. + +3. Verify the load on the TCP endpoint host + - Connect to the host and analyze its resource consumption (CPU, memory, disk I/O, and network bandwidth) with tools like `top`, `vmstat`, `iostat`, and `iftop`. + - Identify resource-consuming processes or applications and apply corrective measures (kill/restart the process, allocate more resources, etc.). + +4. Examine the firewall rules and security groups + - Ensure that there are no blocking rules or security groups for your incoming connections to the TCP endpoint. + - If required, update the rules or create new allow rules for the required ports and IP addresses. + +5. Check the Netdata configuration + - Review the Netdata configuration file `/etc/netdata/netdata.conf` to ensure the `portcheck` plugin settings are correctly configured for monitoring the TCP endpoint. + - If necessary, update and restart the Netdata agent. + +### Useful resources + +1. [Netstat Command in Linux](https://www.tecmint.com/20-netstat-commands-for-linux-network-management/) +2. [Iostat Command Usage and Examples](https://www.thomas-krenn.com/en/wiki/Iostat_command_usage_and_examples) +3. [Iftop Guide](https://www.tecmint.com/iftop-linux-network-bandwidth-monitoring-tool/) -- cgit v1.2.3