From 18c3417bd3cec36f7683925e2a122907666d5c6e Mon Sep 17 00:00:00 2001 From: Guido Trotter Date: Fri, 15 Feb 2013 15:39:06 +0100 Subject: [PATCH] Document possible hypervisor bug in serial_console This is described in Issue 83. Update both the install guide and the gnt-instance manpage. In the install guide move another KVM specific example inside a new KVM admonition for the hypervisor parameters section. Signed-off-by: Guido Trotter Reviewed-by: Iustin Pop --- doc/install.rst | 17 +++++++++++++---- man/gnt-instance.rst | 6 +++++- 2 files changed, 18 insertions(+), 5 deletions(-) diff --git a/doc/install.rst b/doc/install.rst index ec1c6ab..8f753d6 100644 --- a/doc/install.rst +++ b/doc/install.rst @@ -721,10 +721,19 @@ modify``. Your instance types, networking environment, hypervisor type and version may all affect what kind of parameters should be used on your cluster. -For example kvm instances are by default configured to use a host -kernel, and to be reached via serial console, which works nice for Linux -paravirtualized instances. If you want fully virtualized instances you -may want to handle their kernel inside the instance, and to use VNC. +.. admonition:: KVM + + Instances are by default configured to use a host kernel, and to be + reached via serial console, which works nice for Linux paravirtualized + instances. If you want fully virtualized instances you may want to + handle their kernel inside the instance, and to use VNC. + + Some versions of KVM have a bug that will make an instance hang when + configured to use the serial console (which is the default) unless a + connection is made to it within about 2 seconds of the instance's + startup. For such case it's recommended to disable the + ``serial_console`` option. + Joining the nodes to the cluster ++++++++++++++++++++++++++++++++ diff --git a/man/gnt-instance.rst b/man/gnt-instance.rst index 6fe996b..d5c7d09 100644 --- a/man/gnt-instance.rst +++ b/man/gnt-instance.rst @@ -492,7 +492,11 @@ serial\_console Valid for the KVM hypervisor. This boolean option specifies whether to emulate a serial console - for the instance. + for the instance. Note that some versions of KVM have a bug that + will make an instance hang when configured to use the serial console + unless a connection is made to it within about 2 seconds of the + instance's startup. For such case it's recommended to disable this + option, which is enabled by default. serial\_speed Valid for the KVM hypervisor. -- 1.7.10.4