From dc5b148313d80043603a29e1ee7d3560aff3f5a4 Mon Sep 17 00:00:00 2001 From: Brian Shumate Date: Thu, 30 Mar 2017 13:56:03 -0400 Subject: [PATCH] docs: add user resource limits FAQ, fixes #1628 --- website/source/docs/faq.html.markdown | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/website/source/docs/faq.html.markdown b/website/source/docs/faq.html.markdown index 090806f184..cbbfcd1a9f 100644 --- a/website/source/docs/faq.html.markdown +++ b/website/source/docs/faq.html.markdown @@ -82,3 +82,22 @@ as well as race conditions between data updates and watch registrations. ## Q: What network ports does Consul use? The [Ports Used](https://www.consul.io/docs/agent/options.html#ports) section of the Configuration documentation lists all ports that Consul uses. + +## Q: Does Consul require certain user process resource limits? + +There should be only a small number of open file descriptors required for a +Consul client agent. The gossip layers perform transient connections with +other nodes, each connection to the client agent (such as for a blocking +query) will open a connection, and there will typically be connections to one +of the Consul servers. A small number of file descriptors are also required +for watch handlers, health checks, log files, and so on. + +For a Consul server agent, you should plan on the above requirements and +an additional incoming connection from each of the nodes in the cluster. This +should not be the common case, but in the worst case if there is a problem +with the other servers you would expect the other client agents to all +connect to a single server and so preparation for this possibility is helpful. + +The default ulimits are usually sufficient for Consul, but you should closely +scrutinize your own environment's specific needs and identify the root cause +of any excessive resource utilization before arbitrarily increasing the limits.