diff mbox

[v3,1/3] docs: add pod variant of xen-pv-channel.7

Message ID 20170726143950.30329-2-olaf@aepfle.de (mailing list archive)
State New, archived
Headers show

Commit Message

Olaf Hering July 26, 2017, 2:39 p.m. UTC
Convert source for xen-pv-channel.7 from markdown to pod.
This removes the buildtime requirement for pandoc, and subsequently the
need for ghc, in the chain for BuildRequires of xen.rpm.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 docs/man/xen-pv-channel.markdown.7 | 106 ---------------------
 docs/man/xen-pv-channel.pod.7      | 188 +++++++++++++++++++++++++++++++++++++
 2 files changed, 188 insertions(+), 106 deletions(-)
 delete mode 100644 docs/man/xen-pv-channel.markdown.7
 create mode 100644 docs/man/xen-pv-channel.pod.7
diff mbox

Patch

diff --git a/docs/man/xen-pv-channel.markdown.7 b/docs/man/xen-pv-channel.markdown.7
deleted file mode 100644
index 1c6149dae0..0000000000
--- a/docs/man/xen-pv-channel.markdown.7
+++ /dev/null
@@ -1,106 +0,0 @@ 
-Xen PV Channels
-===============
-
-A channel is a low-bandwidth private byte stream similar to a serial
-link. Typical uses of channels are
-
-  1. to provide initial configuration information to a VM on boot
-     (example use: CloudStack's cloud-early-config service)
-  2. to signal/query an in-guest agent
-     (example use: oVirt's guest agent)
-
-Channels are similar to virtio-serial devices and emulated serial links.
-Channels are intended to be used in the implementation of libvirt <channel>s
-when running on Xen.
-
-Note: if an application requires a high-bandwidth link then it should use
-vchan instead.
-
-How to use channels: an example
--------------------------------
-
-Consider a cloud deployment where VMs are cloned from pre-made templates,
-and customised on first boot by an in-guest agent which sets the IP address,
-hostname, ssh keys etc. To install the system the cloud administrator would
-first:
-
-  1. Install a guest as normal (no channel configuration necessary)
-  2. Install the in-guest agent specific to the cloud software. This will
-     prepare the guest to communicate over the channel, and also prepare
-     the guest to be cloned safely (sometimes known as "sysprepping")
-  3. Shutdown the guest
-  4. Register the guest as a template with the cloud orchestration software
-  5. Install the cloud orchestration agent in dom0
-
-At runtime, when a cloud tenant requests that a VM is created from the template,
-the sequence of events would be: (assuming a Linux domU)
-
-  1. A VM is "cloned" from the template
-  2. A unique Unix domain socket path in dom0 is allocated
-     (e.g. /my/cloud/software/talk/to/domain/<vm uuid>)
-  3. Domain configuration is created for the VM, listing the channel
-     name expected by the in-guest agent. In xl syntax this would be:
-
-     channel = [ "connection=socket, name=org.my.cloud.software.agent.version1,
-                  path = /my/cloud/software/talk/to/domain/<vm uuid>" ]
-
-  4. The VM is started
-  5. In dom0 the cloud orchestration agent connects to the Unix domain
-     socket, writes a handshake message and waits for a reply
-  6. Assuming the guest kernel has CONFIG_HVC_XEN_FRONTEND set then the console
-     driver will generate a hotplug event
-  7. A udev rule is activated by the hotplug event.
-
-     The udev rule would look something like:
-
-     SUBSYSTEM=="xen", DEVPATH=="/devices/console-[0-9]", RUN+="xen-console-setup"
-
-     where the "xen-console-setup" script would read the channel name and
-     make a symlink in /dev/xen-channel/org.my.cloud.software.agent.version1
-
-  8. The in-guest agent uses inotify to see the creation of the /dev/xen-channel
-     symlink and opens the device.
-  9. The in-guest agent completes the handshake with the dom0 agent
- 10. The dom0 agent transmits the unique VM configuration: hostname, IP
-     address, ssh keys etc etc
- 11. The in-guest agent receives the configuration and applies it.
-
-Using channels avoids having to use a temporary disk device or network
-connection.
-
-Design recommendations and pitfalls
------------------------------------
-
-It's necessary to install channel-specific software (an "agent") into the guest
-before you can use a channel. By default a channel will appear as a device
-which could be mistaken for a serial port or regular console. It is known
-that some software will proactively seek out serial ports and issue AT commands
-at them; make sure such software is disabled!
-
-Since channels are identified by names, application authors must ensure their
-channel names are unique to avoid clashes. We recommend that channel names
-include parts unique to the application such as a domain names. To assist
-prevent clashes we recommend authors add their names to our global channel
-registry at the end of this document.
-
-Limitations
------------
-
-Hotplug and unplug of channels is not currently implemented.
-
-Channel name registry
----------------------
-
-It is important that channel names are globally unique. To help ensure
-that no-one's name clashes with yours, please add yours to this list.
-
-    Key:
-    N: Name
-    C: Contact
-    D: Short description of use, possibly including a URL to your software
-       or API
-    
-    N: org.xenproject.guest.clipboard.0.1
-    C: David Scott <dave.scott@citrix.com>
-    D: Share clipboard data via an in-guest agent. See:
-       http://wiki.xenproject.org/wiki/Clipboard_sharing_protocol
diff --git a/docs/man/xen-pv-channel.pod.7 b/docs/man/xen-pv-channel.pod.7
new file mode 100644
index 0000000000..2333083cce
--- /dev/null
+++ b/docs/man/xen-pv-channel.pod.7
@@ -0,0 +1,188 @@ 
+=encoding utf8
+
+
+=head1 NAME
+
+Xen PV Channels
+
+=head1 DESCRIPTION
+
+A channel is a low-bandwidth private byte stream similar to a serial
+link. Typical uses of channels are
+
+=over
+
+=item 1.
+
+to provide initial configuration information to a VM on boot
+(example use: CloudStack's cloud-early-config service)
+
+
+=item 2.
+
+to signal/query an in-guest agent
+(example use: oVirt's guest agent)
+
+
+=back
+
+Channels are similar to virtio-serial devices and emulated serial links.
+Channels are intended to be used in the implementation of libvirt s
+when running on Xen.
+
+Note: if an application requires a high-bandwidth link then it should use
+vchan instead.
+
+
+=head2 How to use channels: an example
+
+Consider a cloud deployment where VMs are cloned from pre-made templates,
+and customised on first boot by an in-guest agent which sets the IP address,
+hostname, ssh keys etc. To install the system the cloud administrator would
+first:
+
+=over
+
+=item 1.
+
+Install a guest as normal (no channel configuration necessary)
+
+
+=item 2.
+
+Install the in-guest agent specific to the cloud software. This will
+prepare the guest to communicate over the channel, and also prepare
+the guest to be cloned safely (sometimes known as "sysprepping")
+
+
+=item 3.
+
+Shutdown the guest
+
+
+=item 4.
+
+Register the guest as a template with the cloud orchestration software
+
+
+=item 5.
+
+Install the cloud orchestration agent in dom0
+
+
+=back
+
+At runtime, when a cloud tenant requests that a VM is created from the template,
+the sequence of events would be: (assuming a Linux domU)
+
+=over
+
+=item 1.
+
+A VM is "cloned" from the template
+
+
+=item 2.
+
+A unique Unix domain socket path in dom0 is allocated
+(e.g. /my/cloud/software/talk/to/domain/)
+
+
+=item 3.
+
+Domain configuration is created for the VM, listing the channel
+name expected by the in-guest agent. In xl syntax this would be:
+
+channel = [ "connection=socket, name=org.my.cloud.software.agent.version1, path = /my/cloud/software/talk/to/domain/" ]
+
+=item 4.
+
+The VM is started
+
+
+=item 5.
+
+In dom0 the cloud orchestration agent connects to the Unix domain
+socket, writes a handshake message and waits for a reply
+
+
+=item 6.
+
+Assuming the guest kernel has CONFIGI<HVC>XEN_FRONTEND set then the console
+driver will generate a hotplug event
+
+
+=item 7.
+
+A udev rule is activated by the hotplug event.
+
+The udev rule would look something like:
+
+SUBSYSTEM=="xen", DEVPATH=="/devices/console-[0-9]", RUN+="xen-console-setup"
+
+where the "xen-console-setup" script would read the channel name and
+make a symlink in /dev/xen-channel/org.my.cloud.software.agent.version1
+
+
+=item 8.
+
+The in-guest agent uses inotify to see the creation of the /dev/xen-channel
+symlink and opens the device.
+
+
+=item 9.
+
+The in-guest agent completes the handshake with the dom0 agent
+
+
+=item 10.
+
+The dom0 agent transmits the unique VM configuration: hostname, IP
+address, ssh keys etc etc
+
+
+=item 11.
+
+The in-guest agent receives the configuration and applies it.
+
+
+=back
+
+Using channels avoids having to use a temporary disk device or network
+connection.
+
+
+=head2 Design recommendations and pitfalls
+
+It's necessary to install channel-specific software (an "agent") into the guest
+before you can use a channel. By default a channel will appear as a device
+which could be mistaken for a serial port or regular console. It is known
+that some software will proactively seek out serial ports and issue AT commands
+at them; make sure such software is disabled!
+
+Since channels are identified by names, application authors must ensure their
+channel names are unique to avoid clashes. We recommend that channel names
+include parts unique to the application such as a domain names. To assist
+prevent clashes we recommend authors add their names to our global channel
+registry at the end of this document.
+
+
+=head2 Limitations
+
+Hotplug and unplug of channels is not currently implemented.
+
+
+=head2 Channel name registry
+
+It is important that channel names are globally unique. To help ensure
+that no-one's name clashes with yours, please add yours to this list.
+
+    Key:
+    N: Name
+    C: Contact
+    D: Short description of use, possibly including a URL to your software or API
+
+    N: org.xenproject.guest.clipboard.0.1
+    C: David Scott <dave.scott@citrix.com>
+    D: Share clipboard data via an in-guest agent. See:
+       http://wiki.xenproject.org/wiki/Clipboard_sharing_protocol