From: Fabian Ebner <f.ebner@proxmox.com>
To: pve-devel@lists.proxmox.com
Subject: [pve-devel] [PATCH v2 container 2/2] Improve feedback for startup
Date: Tue, 8 Sep 2020 13:58:43 +0200 [thread overview]
Message-ID: <20200908115843.345-2-f.ebner@proxmox.com> (raw)
In-Reply-To: <20200908115843.345-1-f.ebner@proxmox.com>
Since it was necessary to switch to 'Type=Simple' in the systemd
service, see 545d6f0a13ac2bf3a8d3f224c19c0e0def12116d,
'systemctl start' would not wait for the 'lxc-start' command anymore.
Thus every container start was reported as a success and the 'post-start'
hook would trigger immediately after the 'systemctl start' command.
Use the monitor socket to get the necessary information and detect
startup failure, and only run the 'post-start' hookscript after
the container is effectively running. If something goes wrong
with the monitor socket, for example if lxc-monitord is not running,
fall back to the old behavior.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
---
Changes from v1:
* use monitor socket directly instead of forking off an lxc-monitor process
* use run_with_timeout helper
* warn instead of die on unexpected message
src/PVE/LXC.pm | 40 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 39 insertions(+), 1 deletion(-)
diff --git a/src/PVE/LXC.pm b/src/PVE/LXC.pm
index db5b8ca..370adda 100644
--- a/src/PVE/LXC.pm
+++ b/src/PVE/LXC.pm
@@ -32,6 +32,7 @@ use PVE::LXC::Config;
use PVE::GuestHelpers qw(safe_string_ne safe_num_ne safe_boolean_ne);
use PVE::LXC::Tools;
use PVE::LXC::CGroup;
+use PVE::LXC::Monitor;
use Time::HiRes qw (gettimeofday);
my $have_sdn;
@@ -2191,10 +2192,47 @@ sub vm_start {
PVE::Storage::activate_volumes($storage_cfg, $vollist);
+ my $monitor_socket = eval { PVE::LXC::Monitor::get_monitor_socket(); };
+ warn $@ if $@;
+
+ my $monitor_state_change = sub {
+ die "no monitor socket" if !defined($monitor_socket);
+
+ while (1) {
+ my ($type, $name, $value) = PVE::LXC::Monitor::read_lxc_message($monitor_socket);
+
+ die "monitor socket EOF" if !defined($type);
+
+ next if $name ne "$vmid" || $type ne 'STATE';
+
+ if ($value eq PVE::LXC::Monitor::STATE_STARTING) {
+ alarm(0); # don't timeout after seeing the starting state
+ } elsif ($value eq PVE::LXC::Monitor::STATE_ABORTING ||
+ $value eq PVE::LXC::Monitor::STATE_STOPPING ||
+ $value eq PVE::LXC::Monitor::STATE_STOPPED) {
+ return 0;
+ } elsif ($value eq PVE::LXC::Monitor::STATE_RUNNING) {
+ return 1;
+ } else {
+ warn "unexpected message from monitor socket - " .
+ "type: '$type' - value: '$value'\n";
+ }
+ }
+ };
+
my $cmd = ['systemctl', 'start', "pve-container\@$vmid"];
PVE::GuestHelpers::exec_hookscript($conf, $vmid, 'pre-start', 1);
- eval { PVE::Tools::run_command($cmd); };
+ eval {
+ PVE::Tools::run_command($cmd);
+
+ my $success = eval { PVE::Tools::run_with_timeout(10, $monitor_state_change); };
+ if (my $err = $@) {
+ warn "problem with monitor socket: $err - continuing anyway\n";
+ } elsif (!$success) {
+ die "startup for container '$vmid' failed\n";
+ }
+ };
if (my $err = $@) {
unlink $skiplock_flag_fn;
die $err;
--
2.20.1
next prev parent reply other threads:[~2020-09-08 11:59 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-08 11:58 [pve-devel] [PATCH v2 container 1/2] Add module for reading state changes from monitor socket Fabian Ebner
2020-09-08 11:58 ` Fabian Ebner [this message]
2020-09-09 19:09 ` [pve-devel] applied-series: " Thomas Lamprecht
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