From 96fbd74d6d70b562f45e327eeb0f625b54899bcc Mon Sep 17 00:00:00 2001 From: Laurent Bercot Date: Sat, 4 Jul 2015 01:40:10 +0000 Subject: Start of doc --- doc/s6-rc-upgrade.html | 174 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 174 insertions(+) create mode 100644 doc/s6-rc-upgrade.html (limited to 'doc/s6-rc-upgrade.html') diff --git a/doc/s6-rc-upgrade.html b/doc/s6-rc-upgrade.html new file mode 100644 index 0000000..bdaa090 --- /dev/null +++ b/doc/s6-rc-upgrade.html @@ -0,0 +1,174 @@ + + + + + + s6-rc: the s6-rc-update program + + + + + + +

+s6-rc
+Software
+skarnet.org +

+ +

The s6-rc-update program

+ +

+ s6-rc-update is an online service database switcher: +it will replace your compiled service database with another +one, and adjust the live state accordingly. +

+ +

+ Live upgrading a service database is no small feat, and no +fully automated system can get it right in all cases. +s6-rc-update will do its best on its own, but it lets you +give it instructions to handle +difficult cases; and rather than implement doubtful +heuristics, it will fail with an error message in +situations it really cannot solve. +

+ +

Interface

+ +

+     s6-rc [ -v verbosity ] [ servicenames... ]
+

+ +

s6-rc expects to find a compiled service database +in /etc/s6-rc/compiled and a live state in +/s6/s6-rc. If it cannot find that data, it complains and +exits. +
- The compiled service database is built offline +via the s6-rc-compile tool.
- The live state should be initialized at boot time +via the s6-rc-init tool. It is then +maintained by s6-rc itself.
The command line arguments servicenames... define a set +of selected services the user wants to act on.
s6-rc computes the necessary transitions to bring the machine +to the desired state - by default a state where all the +services listed on the command line are up. If asked to, it performs +those transitions.
s6-rc processes services as soon as they can be processed. It +will wait until a service is up to start a dependent service, but it +will start two independent services in parallel.
If every state transition completes successfully, s6-rc exits 0.
If a state transition fails, s6-rc will not perform the transitions +that depend on it. It will wait until all the other independent transitions +are done, then exit 1.

+ +

Options

+ +

s6-rc control

+ +

-v verbosity : be more or less +verbose. Default is 1: warning and error messages will be printed to +stderr. 0 silences warnings. 2 writes information messages whenever +s6-rc performs a transition. 3 or more is debug info.
-n dryruntimeout : dry run. +s6-rc will pretend to perform transitions, but will replace all its +program invocations by a call to +s6-rc-dryrun, which will do nothing but +print the command line s6-rc would have executed, then sleep for +dryruntimeout milliseconds before reporting success.
-t timeout : timeout. If s6-rc +isn't done after timeout milliseconds, it will exit, leaving +the live state as it is at exit time. It does not kill its children, so +a child may successfully complete afterwards and the live state will +not be updated; in that case, subsequent s6-rc invocations will notice +and correctly update it.
-c compiled : look for the +compiled service database in compiled. Default is +/etc/s6-rc/compiled
-l live : look for the +live state in live. Default is +/s6/s6-rc

+ +

Up or down

+ +

-u : selected services are interpreted +as to be brought up. This is the default.
-d : selected services are interpreted +as to be brought down.

+ +

Service selection

+ +

-p : prune. The state will be brought to +exactly servicenames..., plus their dependencies, and +the other services will be brought down. With the -d option, +the meaning is reversed: the state will be brought to the maximum +possible set that does not include servicenames....
-a : all. Add the current set of active services to +the selected set. This is useful to ensure consistency of the machine +state, for instance, and also at shutdown time: s6-rc -da +will stop all the currently active services.

+ +

Actions

+ +

-C : check. s6-rc will check the consistency of the +database, and exit with an error message if it finds errors.
-L : list. s6-rc will resolve the given names, then +print the list of corresponding atomic services to stdout, without taking their +dependencies into account. It will print an empty line afterwards.
-A : list all. s6-rc will print the list of selected +atomic services to stdout, after computing dependencies. Note that with +the -d option, it computes reverse dependencies instead.
-S : state change. A state change will be performed +for the selected services. +This is the default if no other action option has been given.

+ +

Usage examples

+ +

 s6-rc myservicebundle

+ Brings up all the services represented by myservicebundle, +dependencies first. +

+ +

 s6-rc -Sad

+ Brings down all the services in an orderly manner. This is typically +run at shutdown time. +

+ +

 s6-rc -Au myservicebundle

+ Prints the names of all atomic services represented by +myservicebundle, as well as everything they depend on. +

+ +

 s6-rc -Ad myservicebundle

+ Prints the names of all atomic services represented by +myservicebundle, as well as everything that depends on them. +

+ +

 s6-rc -pun0 myservicebundle

+ Prints what s6-rc would do to bring the state to just +myservicebundle and its dependencies. +

+ + +

Internals

+ + + -- cgit v1.2.3