Difference between revisions of "Upstart issues"
From Linux-VServer
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initctl emit filesystem | initctl emit filesystem | ||
end script | end script | ||
| + | |||
| + | === Notes for older kernels === | ||
| + | If you encounter upstart errors like this: | ||
| + | |||
| + | $ vserver foo start | ||
| + | init: missing runlevel | ||
| + | Try `init --help' for more information. | ||
| + | |||
| + | or | ||
| + | |||
| + | $ vserver foo start | ||
| + | telinit: Failed to connect to socket /com/ubuntu/upstart: Connection refused | ||
| + | |||
| + | then you're probably running the current stable version <code>2.6.22.19-vs2.2.0.7</code>. | ||
| + | |||
| + | Upstart's <code>/sbin/init</code> implementation requires to be PID 1. It is linked against NPTL (in contrast to sysvinit), which has a bug in it's caching <code>getpid(2)</code> wrapper. With this kernel version <code>getpid(2)</code> returns the cached PID to init, resulting in init replacing itself with telinit. You can fix this by upgrading to a <code>2.6.26+</code> kernel and a newer vserver patch, or by patching upstart: | ||
| + | |||
| + | diff --git a/init/main.c b/init/main.c | ||
| + | index bfcd528..c6c9304 100644 | ||
| + | --- a/init/main.c | ||
| + | +++ b/init/main.c | ||
| + | @@ -37,6 +37,7 @@ | ||
| + | #include <string.h> | ||
| + | #include <syslog.h> | ||
| + | #include <unistd.h> | ||
| + | +#include <syscall.h> | ||
| + | |||
| + | #include <linux/kd.h> | ||
| + | |||
| + | @@ -131,7 +132,7 @@ main (int argc, | ||
| + | } | ||
| + | |||
| + | /* Check we're process #1 */ | ||
| + | - if (getpid () > 1) { | ||
| + | + if (syscall(SYS_getpid) > 1) { | ||
| + | execv (TELINIT, argv); | ||
| + | /* Ignore failure, probably just that telinit doesn't exist */ | ||
| + | |||
| + | For more information see the man pages of <code>getpid(2)</code> (NOTES) and <code>clone(2)</code> (BUGS). | ||
Revision as of 03:11, 16 November 2009
Contents |
running an upstart based guest
currently upstart based guests need some manual tweaking to make them work inside a vserver guest.
prepare the host
First of all you need to set the init style of your vserver to plain
# echo plain > /etc/vservers/<vservername>/apps/init/style
remove low level services inside the guest
Then you need to get rid of anything in /etc/init/ that tries to fiddle with your Server's Hardware or other low-level Stuff that's already handled by your host's kernel/system. Having one such scriptlet still enabled might cause the whole upstart system to fail (like not beeing able to open /dev/console or failing to start the udev system).
Just remove these scriptlets, move them out of the way or rename them to something not ending in .conf. Be aware that upstart also parses subfolders of /etc/init/ for .conf files.
This is what I deleted on a basic Ubuntu 9.10 guest:
dmesg.conf hostname.conf hwclock-save.conf hwclock.conf mountall-net.conf mountall-reboot.conf mountall-shell.conf mountall.conf network-interface.conf networking.conf procps.conf rsyslog-kmsg.conf tty1.conf tty2.conf tty3.conf tty4.conf tty5.conf tty6.conf upstart-udev-bridge.conf
fake low level events inside the guest
Finally you need to fake emit the events that some of these scripts would do during regular boot. Probably the cleanest approach is to add a scriptlet vserver.conf to /etc/init/ with this content:
start on startup
script
initctl emit virtual-filesystems
initctl emit local-filesystems
initctl emit remote-filesystems
initctl emit filesystem
end script
Notes for older kernels
If you encounter upstart errors like this:
$ vserver foo start init: missing runlevel Try `init --help' for more information.
or
$ vserver foo start telinit: Failed to connect to socket /com/ubuntu/upstart: Connection refused
then you're probably running the current stable version 2.6.22.19-vs2.2.0.7.
Upstart's /sbin/init implementation requires to be PID 1. It is linked against NPTL (in contrast to sysvinit), which has a bug in it's caching getpid(2) wrapper. With this kernel version getpid(2) returns the cached PID to init, resulting in init replacing itself with telinit. You can fix this by upgrading to a 2.6.26+ kernel and a newer vserver patch, or by patching upstart:
diff --git a/init/main.c b/init/main.c
index bfcd528..c6c9304 100644
--- a/init/main.c
+++ b/init/main.c
@@ -37,6 +37,7 @@
#include <string.h>
#include <syslog.h>
#include <unistd.h>
+#include <syscall.h>
#include <linux/kd.h>
@@ -131,7 +132,7 @@ main (int argc,
}
/* Check we're process #1 */
- if (getpid () > 1) {
+ if (syscall(SYS_getpid) > 1) {
execv (TELINIT, argv);
/* Ignore failure, probably just that telinit doesn't exist */
For more information see the man pages of getpid(2) (NOTES) and clone(2) (BUGS).
