From b485aab7e71c1625cfc27e0f92c9509f42378458 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 5 May 2024 13:19:16 +0200 Subject: Adding upstream version 1.45.3+dfsg. Signed-off-by: Daniel Baumann --- src/health/guides/ping/ping_host_reachable.md | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 src/health/guides/ping/ping_host_reachable.md (limited to 'src/health/guides/ping/ping_host_reachable.md') diff --git a/src/health/guides/ping/ping_host_reachable.md b/src/health/guides/ping/ping_host_reachable.md new file mode 100644 index 000000000..75e24cbee --- /dev/null +++ b/src/health/guides/ping/ping_host_reachable.md @@ -0,0 +1,27 @@ +### Understand the alert + +This `ping_host_reachable` alert checks the network reachability status of a specific host. When you receive this alert, it means that the host is either `up` (reachable) or `down` (unreachable). + +### What is network reachability? + +Network reachability refers to the ability of a particular host to communicate with other devices or systems within a network. In this alert, the reachability is monitored using the `ping` command, which sends packets to the host and checks for the response. The alert evaluates the packet loss percentage over a 30-second period. + +### Troubleshoot the alert + +1. Verify if the alert is accurate: Check if there are transient network issues or if there is a problem with the particular host. You can run the `ping` command manually to see if the packet loss percentage is consistent over time. + + ``` + ping -c 10 + ``` + +2. Check the network connectivity: Ensure there are no issues with the local network or the physical connections (switches, routers, etc.). Look for potential network bottlenecks, high traffic, and hardware failures that can affect reachability. + +3. Check the host's health: If the host is reachable, log in to the system and examine its performance, stability, and resource usage. Look for indicators of high system load, resource constraints, or unresponsive processes. + +4. Examine network security policies and firewalls: Network reachability can be affected by misconfigured firewalls or security policies. Ensure there are no restrictions blocking the communication between the monitoring system and the host. + +5. Analyze logs for any relevant information: Check system logs (e.g., `/var/log/syslog`) and application logs on both the monitoring system and the target host. Look for error messages, timeouts, or connectivity problems. + +### Useful resources + +1. [Understanding High Packet Loss in Networking](https://www.fiberplex.com/blog/understanding-high-packet-loss-in-networking) -- cgit v1.2.3