Documentation: include the cluster id namespace explanation on the

[arvados.git] / doc / install / install-manual-prerequisites.html.textile.liquid

diff --git a/doc/install/install-manual-prerequisites.html.textile.liquid b/doc/install/install-manual-prerequisites.html.textile.liquid
index 8f45b29a4f6b98bdbacd73290ae7b1d34364700e..364e8cd2bb2267e119961042e05a38f9eebb9b3f 100644 (file)
--- a/doc/install/install-manual-prerequisites.html.textile.liquid
+++ b/doc/install/install-manual-prerequisites.html.textile.liquid
@@ -119,7 +119,13 @@ For a small demo installation, it is possible to run all the Arvados services on
 
 h2(#clusterid). Arvados Cluster ID
 
-Each Arvados installation should have a cluster identifier, which is a unique 5-character lowercase alphanumeric string.   Here is one way to make a random 5-character string:
+Each Arvados installation is identified by a cluster identifier, which is a unique 5-character lowercase alphanumeric string. There are 36 5 = 60466176 possible cluster identifiers.
+
+* For automated test purposes, use “z****”
+* For experimental/local-only/private clusters that won’t ever be visible on the public Internet, use “x****”
+* For long-lived clusters, we recommend reserving a cluster id.  Contact "info@curii.com":mailto:info@curii.com for more information.
+
+Here is one way to make a random 5-character string:
 
 <notextile>
 <pre><code>~$ <span class="userinput">tr -dc 0-9a-z &lt;/dev/urandom | head -c5; echo</span>