From 2a50e2e8c22142023d92d827993dd02f6c5d8210 Mon Sep 17 00:00:00 2001
From: Guido Trotter <ultrotter@google.com>
Date: Fri, 27 Jan 2012 13:35:47 +0000
Subject: [PATCH] walkthrough.rst: updates for maxmem/minmem
- Fix two example outputs
- Improve N+1 resolution section specifying how different memories
affect N+1 calculation depending on the node
Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>
---
doc/walkthrough.rst | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)
diff --git a/doc/walkthrough.rst b/doc/walkthrough.rst
index 071936091..0f26cff02 100644
--- a/doc/walkthrough.rst
+++ b/doc/walkthrough.rst
@@ -478,7 +478,8 @@ redundancy::
- initrd_path: default ()
Hardware:
- VCPUs: 1
- - memory: 128MiB
+ - maxmem: 256MiB
+ - minmem: 512MiB
- NICs:
- nic/0: MAC: aa:00:00:78:da:63, IP: None, mode: bridged, link: xen-br0
Disks:
@@ -857,7 +858,8 @@ with 12GB of RAM (numbers chosen so that we run out of memory)::
node1# gnt-instance modify -B memory=4G instance1
Modified instance instance1
- - be/memory -> 4096
+ - be/maxmem -> 4096
+ - be/minmem -> 4096
Please don't forget that these parameters take effect only at the next start of the instance.
node1# gnt-instance modify β¦
@@ -915,8 +917,15 @@ solve this, you have a number of options:
- try to manually move instances around (but this can become complicated
for any non-trivial cluster)
-- try to reduce memory of some instances to accommodate the available
- node memory
+- try to reduce the minimum memory of some instances on the source node
+ of the N+1 failure (in the example above ``node1``): this will allow
+ it to start and be failed over/migrated with less than its maximum
+ memory
+- try to reduce the runtime/maximum memory of some instances on the
+ destination node of the N+1 failure (in the example above ``node2``)
+ to create additional available node memory (check the :doc:`admin`
+ guide for what Ganeti will and won't automatically do in regards to
+ instance runtime memory modification)
- if Ganeti has been built with the htools package enabled, you can run
the ``hbal`` tool which will try to compute an automated cluster
solution that complies with the N+1 rule
--
GitLab