We've seen this function report "Unknown family, 0" and then CTDB
disappeared without a trace. If we can reproduce it then this might
help us to debug it.
The idea is that you do something like the following in /etc/sysconfig/ctdb:
export CTDB_EXTERNAL_TRACE="/etc/ctdb/config/gcore_trace.sh"
When we hit this error than we call out to gcore to get a core file so
we can do forensics. This might block CTDB for a few seconds.
Signed-off-by: Martin Schwenke <martin@meltin.net>
(This used to be ctdb commit
7895bc003f087ab2f3181df3c464386f59bfcc39)
if [ ! -f $(DESTDIR)$(etcdir)/ctdb/notify.sh ];then ${INSTALLCMD} -m 755 config/notify.sh $(DESTDIR)$(etcdir)/ctdb; fi
${INSTALLCMD} -m 755 config/debug-hung-script.sh $(DESTDIR)$(etcdir)/ctdb
if [ ! -f $(DESTDIR)$(etcdir)/ctdb/ctdb-crash-cleanup.sh ];then ${INSTALLCMD} -m 755 config/ctdb-crash-cleanup.sh $(DESTDIR)$(etcdir)/ctdb; fi
+ if [ ! -f $(DESTDIR)$(etcdir)/ctdb/gcore_trace.sh ];then ${INSTALLCMD} -m 755 config/gcore_trace.sh $(DESTDIR)$(etcdir)/ctdb; fi
install_pmda:
$(INSTALLCMD) -m 755 -d $(PMDA_DEST_DIR)
abort();
}
+/* Invoke an external program to do some sort of tracing on the CTDB
+ * process. This might block for a little while. The external
+ * program is specified by the environment variable
+ * CTDB_EXTERNAL_TRACE. This program should take one argument: the
+ * pid of the process to trace. Commonly, the program would be a
+ * wrapper script around gcore.
+ */
+void ctdb_external_trace(void)
+{
+
+ const char * t = getenv("CTDB_EXTERNAL_TRACE");
+ char * cmd;
+
+ if (t == NULL) {
+ return;
+ }
+
+ cmd = talloc_asprintf(NULL, "%s %lu", t, (unsigned long) getpid());
+ DEBUG(DEBUG_WARNING,("begin external trace: %s\n", cmd));
+ system(cmd);
+ DEBUG(DEBUG_WARNING,("end external trace: %s\n", cmd));
+ talloc_free(cmd);
+}
+
/*
parse a IP:port pair
*/
break;
default:
DEBUG(DEBUG_ERR, (__location__ " ERROR, unknown family %u\n", addr->sa.sa_family));
+ ctdb_external_trace();
}
return cip;
--- /dev/null
+#!/bin/sh
+
+gcore -o "/var/log/core" "$1" 2>&1 | logger -t "ctdb:gcore_trace"
/* internal prototypes */
void ctdb_set_error(struct ctdb_context *ctdb, const char *fmt, ...) PRINTF_ATTRIBUTE(2,3);
void ctdb_fatal(struct ctdb_context *ctdb, const char *msg);
+void ctdb_external_trace(void);
bool ctdb_same_address(struct ctdb_address *a1, struct ctdb_address *a2);
int ctdb_parse_address(struct ctdb_context *ctdb,
TALLOC_CTX *mem_ctx, const char *str,
%config(noreplace) %{_sysconfdir}/ctdb/notify.sh
%config(noreplace) %{_sysconfdir}/ctdb/debug-hung-script.sh
%config(noreplace) %{_sysconfdir}/ctdb/ctdb-crash-cleanup.sh
+%config(noreplace) %{_sysconfdir}/ctdb/gcore_trace.sh
%config(noreplace) %{_sysconfdir}/ctdb/functions
%attr(755,root,root) %{initdir}/ctdb