From bb0efa2a5d4e30636b328d27c76f204a0f40407f Mon Sep 17 00:00:00 2001 From: Michael Johnson Date: Wed, 12 Feb 2020 08:34:51 -0800 Subject: [PATCH] Add docs warning for PING health monitors This patch adds a warning box to the load balancer cookbook clarifying that the health monitor type of 'PING' should only be used in specific cases. This was called out in release notes, but was not clear in the cookbook. Change-Id: I6b95891bec82e01c44b288cbe9796b1f87a07c32 --- doc/source/user/guides/basic-cookbook.rst | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/doc/source/user/guides/basic-cookbook.rst b/doc/source/user/guides/basic-cookbook.rst index 444c773c4b..5c16e7be54 100644 --- a/doc/source/user/guides/basic-cookbook.rst +++ b/doc/source/user/guides/basic-cookbook.rst @@ -822,6 +822,14 @@ and ``UDP-CONNECT``. servers. Obviously, your back-end servers must be configured to allow PINGs in order for these health checks to pass. +.. warning:: + + Health monitors of type ``PING`` only check if the member is reachable and + responds to ICMP echo requests. It will not detect if your application + running on that instance is healthy or not. Most pools should use one of + the other health monitor options. ``PING`` should only be used in specific + cases where an ICMP echo request is a valid health check. + ``TCP`` health monitors open a TCP connection to the back-end server's protocol port. Your custom TCP application should be written to respond OK to the load balancer connecting, opening a TCP connection, and closing it again after the