X-Git-Url: https://git.rrq.au/?a=blobdiff_plain;f=overlay-boot.8.adoc;h=b2a103299a5c690acbae5a1a0c5c44a6c570004d;hb=03fde40e424f449064ac214be1d1fb499b42146e;hp=932cae0b8310cf4e3bb6a57061d374b4ea42a930;hpb=f86ce1827c0f74b3ac15598946b41477dd5a4066;p=rrq%2Foverlay-boot.git

diff --git a/overlay-boot.8.adoc b/overlay-boot.8.adoc
index 932cae0..b2a1032 100644
--- a/overlay-boot.8.adoc
+++ b/overlay-boot.8.adoc
@@ -24,7 +24,7 @@ an overlay of the main host filesystem to keep the specifics of a
 service distinctly separate from the main host while sharing files
 wherever sensible.
 
-A subhost is started by identifyinf its configuration file on the
+A subhost is started by identifying its configuration file on the
 command line for *overlay-boot*. The configuration file is a plain
 text file with a small collection of "variables" that tell how the
 subhost is set up. When all is good, *overlay-boot* spawns a
@@ -34,7 +34,7 @@ odd computer.
 
 The subhost execution environment may be "entered" to perform
 adminstrative tasks with *overlay-go*, and it is later stopped with
-*overlay-stop*.
+*overlay-stop*. 
 
 OPTIONS
 -------
@@ -117,11 +117,11 @@ before the services are started. The default for this variable is
 This variable nominates the "upper" filesystem for an overlay mount.
 This will be accessed read-write and it constitutes the "private"
 files of the subhost.
-
++
 If UPPER is different from LOWER, then the root file system is set up
 as an overlay mount. In that case WORK (below) must be defined as a
 directory outside of but on the same mount as UPPER.
-
++
 If UPPER is the same as LOWER, then the subhost root filesystem is not
 setup as an overla. Rather it is set up as a bind mount, if UPPER is
 different from LIVE, or just as a pre-mounted LIVE filesystem.
@@ -136,7 +136,7 @@ directory.
 
 This variable tells which services should be started on the
 overlay-boot startup. The default value is +networking ssh+.
-
++
 Note that if no services are started, then +overlay-init+ starts a
 +dummy_service+ so as to keep +/.reaper+ from running out of child
 processes, as it otherwise will exit and thereby terminate
@@ -151,16 +151,16 @@ defult gets mounted on an overlay mount as a +tmpfs+ of 50M. Use
 Networking
 ----------
 
-*overlay-boot* sets up a nework namespace named by the subhost NAME,
-and uses the CABLES variable to set up +veth+ virtual cables. The host
-end of such cables are named by NAME followed by a number from 0 and
-up while the subhost end are named by +eth+ followed by the same
-number.
+*overlay-boot* sets up a nework namespace named by the subhost
++$NAME+, and uses the +$CABLES+ variable to set up +veth+ virtual
+cables. The host end of such cables are named by +$NAME+ followed by a
+number from 0 and up while the subhost end are named by +eth+ followed
+by the same number.
 
-As mentioned above, CABLES consists of a space separated list of cable
-specifiers, each consisting of a bridge interface name and a with an
-equal sign ("=") between them. The equal sign is required while either
-or both of the bridge and MAC address may be left empty.
+As mentioned above, +$CABLES+ consists of a space separated list of
+cable specifiers, each consisting of a bridge interface name and a
+with an equal sign ("=") between them. The equal sign is required
+while either or both of the bridge and MAC address may be left empty.
 
 The bridge interface name, if given, will be given control of the host
 end cable interface. A cable specification with empty bridge name part
@@ -177,9 +177,11 @@ EXAMPLES
 
 ./opt/subhost/mta/mta.conf
 ****
+----
 BASE=.
 CABLES= =
-START= rsyslog newtorking ssh postfix
+START= rsyslog networking ssh saslauthd postfix dovecot
+----
 ****
 
 The above example assumes a directory +/opt/subhost/mta+ that contains
@@ -192,5 +194,26 @@ and the main host end is named +mta0+, and upon start, an +ifup mta0+
 is attempted at the host end while the subhost end is handled via its
 neworking service.
 
+./opt/subhost/tiny/tiny.conf
+****
+----
+BASE=.
+CABLES= =
+START= none
+LOWER=!mkdir -p base work root live ; echo base
+WORK= work
+UPPER= root
+LIVE= live
+----
+****
+
+The +tiny+ subhost would be for overlaying a separate +debootstrap+
+root filesystem, without any services (since +START+ is empty). This
+gets started with a +dummy_service+ to hold the overlay for access via
++overlay-go+. The +dummy_service+ sets up and listens on a pipe at
++/run/dummy_service+, and exits when anything is written to that.
 
+SEE ALSO
+--------
 
+*overlay-stop*, *overlay-go*