[Cluster-devel] cluster4 dlm dlm_stonith – should it really fence by turning node off?
Hello, The dlm_stonith fencing helper is really convenient when Pacemaker is in use. Though, it doesn't quite work as I would expect – when fencing is needed it requests a node to be turned off instead of rebooting. And it doesn't handle unfencing – so automatic recovery is not possible (rebooted node could join the cluster cleanly later, provided quorum handling is properly configured in the cluster stack). Preferably this behaviour should be configurable. I have hacked a work-around by (ab)using argv[0] – when 'dlm_stonith' is called as 'dlm_stonith_reboot' the node would be rebooted instead of halting – this works for me well-enough, but I don't think this is the right solution. Any ideas how to solve that properly? An argument for the helper to be included in the config file? Or, maybe, just change the default behaviour? Greets, Jacek
[Cluster-devel] [PATCH 1/2] --foreground option added to dlm_controld
Foreground is the preferred way to run services from systemd
and it is easier to provide startup notification this way.
Signed-off-by: Jacek Konieczny jaj...@jajcus.net
---
dlm_controld/dlm_controld.8 |3 +++
dlm_controld/dlm_daemon.h |1 +
dlm_controld/main.c |7 ++-
3 files changed, 10 insertions(+), 1 deletions(-)
diff --git a/dlm_controld/dlm_controld.8 b/dlm_controld/dlm_controld.8
index 262ef8a..c9011fd 100644
--- a/dlm_controld/dlm_controld.8
+++ b/dlm_controld/dlm_controld.8
@@ -23,6 +23,9 @@ For default settings, see dlm_controld -h.
.B --daemon_debug | -D
enable debugging to stderr and don't fork
+.B --foreground
+don't fork
+
.B --log_debug | -K
enable kernel dlm debugging messages
diff --git a/dlm_controld/dlm_daemon.h b/dlm_controld/dlm_daemon.h
index 916ee58..377f28d 100644
--- a/dlm_controld/dlm_daemon.h
+++ b/dlm_controld/dlm_daemon.h
@@ -109,6 +109,7 @@ enum {
enable_quorum_lockspace_ind,
help_ind,
version_ind,
+foreground_ind,
dlm_options_max,
};
diff --git a/dlm_controld/main.c b/dlm_controld/main.c
index fd469f9..deda60c 100644
--- a/dlm_controld/main.c
+++ b/dlm_controld/main.c
@@ -1245,6 +1245,11 @@ static void set_opt_defaults(void)
0, NULL,
enable debugging to stderr and don't fork);
+ set_opt_default(foreground_ind,
+ foreground, '\0', no_arg,
+ 0, NULL,
+ don't fork);
+
set_opt_default(log_debug_ind,
log_debug, 'K', no_arg,
0, NULL,
@@ -1562,7 +1567,7 @@ int main(int argc, char **argv)
INIT_LIST_HEAD(fs_register_list);
init_daemon();
- if (!opt(daemon_debug_ind)) {
+ if (!opt(daemon_debug_ind) !opt(foreground_ind)) {
if (daemon(0, 0) 0) {
perror(daemon error);
exit(EXIT_FAILURE);
--
1.7.7.4
[Cluster-devel] cluster4 dlm: startup notification for systemd
Hello, The two patches: [PATCH 1/2] --foreground option added to dlm_controld [PATCH 2/2] Startup notification by sd_notify() add startup notification for the systemd service unit. This way startup of services depending on DLM can be properly serialized. Currently dlm_controld forks immediately and the parent exits befor the DLM subsystem is properly initialized. If clvmd is started next, it will fail with some cryptic error messages (like 'dlm: no local IP address has been set'). With the startup notification clvmd startup can be delayed until dlm_controld reports it is ready. Similar thing could be implemented with forking and no external dependency, – but that is a bit more complicated, as requires communication between the parent and child process or moving the initialization code before fork(). sd_notify() could also be used to provide status information during the start-up phase too, but I am not familiar enough with what is happening there to provide reasonable status messages. Greets, Jacek
[Cluster-devel] [PATCH 2/2] Startup notification by sd_notify()
Implements simple start-up status notification via the sd_notify(3)
function from the libsystemd-daemon library. This allows proper
service startup serialization by the init daemon – services depending
on DLM will be started after dlm_controld completes the initialization.
As this pulls additional dependency, the feature my by disabled on
compile time by calling 'make' with 'USE_SD_NOTIFY=no'.
Signed-off-by: Jacek Konieczny jaj...@jajcus.net
---
dlm_controld/Makefile |8
dlm_controld/main.c |8
init/dlm.service |5 +++--
3 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/dlm_controld/Makefile b/dlm_controld/Makefile
index f42a913..13d6339 100644
--- a/dlm_controld/Makefile
+++ b/dlm_controld/Makefile
@@ -6,6 +6,8 @@ LIBDIR=$(PREFIX)/$(LIBNUM)
HDRDIR=$(PREFIX)/include
MANDIR=$(PREFIX)/share/man
+USE_SD_NOTIFY=yes
+
BIN_TARGET = dlm_controld
LIB_NAME = libdlmcontrol
@@ -59,6 +61,12 @@ BIN_LDFLAGS += -lpthread -lrt -lcpg -lcmap -lcfg -lquorum
LIB_CFLAGS += $(BIN_CFLAGS)
LIB_LDFLAGS += -Wl,-z,relro -pie
+ifeq ($(USE_SD_NOTIFY),yes)
+ BIN_CFLAGS += $(shell pkg-config --cflags libsystemd-daemon) \
+ -DUSE_SD_NOTIFY
+ BIN_LDFLAGS += $(shell pkg-config --libs libsystemd-daemon)
+endif
+
all: $(LIB_TARGET) $(BIN_TARGET)
$(BIN_TARGET): $(BIN_SOURCE)
diff --git a/dlm_controld/main.c b/dlm_controld/main.c
index deda60c..d1fdb2a 100644
--- a/dlm_controld/main.c
+++ b/dlm_controld/main.c
@@ -14,6 +14,10 @@
#include linux/genetlink.h
#include linux/dlm_netlink.h
+#ifdef USE_SD_NOTIFY
+#include systemd/sd-daemon.h
+#endif
+
#include copyright.cf
#include version.cf
@@ -1012,6 +1016,10 @@ static void loop(void)
plock_fd = rv;
plock_ci = client_add(rv, process_plocks, NULL);
+#ifdef USE_SD_NOTIFY
+ sd_notify(0, READY=1);
+#endif
+
for (;;) {
rv = poll(pollfd, client_maxi + 1, poll_timeout);
if (rv == -1 errno == EINTR) {
diff --git a/init/dlm.service b/init/dlm.service
index 3c4e53e..f068c63 100644
--- a/init/dlm.service
+++ b/init/dlm.service
@@ -3,10 +3,11 @@ Description=dlm control daemon
After=syslog.target network.target corosync.service sys-kernel-config.mount
[Service]
-Type=forking
+Type=notify
+NotifyAccess=main
EnvironmentFile=/etc/sysconfig/dlm
ExecStartPre=/sbin/modprobe dlm
-ExecStart=/usr/sbin/dlm_controld $DLM_CONTROLD_OPTS
+ExecStart=/usr/sbin/dlm_controld --foreground $DLM_CONTROLD_OPTS
#ExecStopPost=/sbin/modprobe -r dlm
[Install]
--
1.7.7.4
