mdctl-0.5mdctl-0.5

1 files changed, 211 insertions, 0 deletions

diff --git a/Monitor.c b/Monitor.c
new file mode 100644
index 0000000..968e4b3
--- /dev/null
+++ b/Monitor.c
@@ -0,0 +1,211 @@
+/*
+ * mdctl - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2001 Neil Brown <neilb@cse.unsw.edu.au>
+ *
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *    Author: Neil Brown
+ *    Email: <neilb@cse.unsw.edu.au>
+ *    Paper: Neil Brown
+ *           School of Computer Science and Engineering
+ *           The University of New South Wales
+ *           Sydney, 2052
+ *           Australia
+ */
+
+#include	"mdctl.h"
+#include	"md_p.h"
+#include	"md_u.h"
+#include	<sys/signal.h>
+
+static void alert(char *event, char *dev, char *disc, char *mailaddr, char *cmd);
+
+int Monitor(int num_devs, char *devlist[],
+	    char *mailaddr, char *alert_cmd,
+	    int period,
+	    char *config)
+{
+	/*
+	 * Every few seconds, scan every md device looking for changes
+	 * When a change is found, log it, possibly run the alert command,
+	 * and possibly send Email
+	 *
+	 * For each array, we record:
+	 *   Update time
+	 *   active/working/failed/spare drives
+	 *   State of each device.
+	 *
+	 * If the update time changes, check out all the data again
+	 * It is possible that we cannot get the state of each device
+	 * due to bugs in the md kernel module.
+	 *
+	 * if active_drives decreases, generate a "Fail" event
+	 * if active_drives increases, generate a "SpareActive" event
+	 *
+	 * if we detect an array with active<raid and spare==0
+	 * we look at other arrays that have same spare-group
+	 * If we find one with active==raid and spare>0,
+	 *  and if we can get_disk_info and find a name
+	 *  Then we hot-remove and hot-add to the other array
+	 *
+	 */
+
+	struct state {
+		char *devname;
+		long utime;
+		int err;
+		int active, working, failed, spare;
+		int devstate[MD_SB_DISKS];
+		struct state *next;
+	} *statelist = NULL;
+	int finished = 0;
+	while (! finished) {
+		mddev_ident_t mdlist = NULL;
+		int dnum=0;
+		if (num_devs == 0)
+			mdlist = conf_get_ident(config, NULL);
+		while (dnum < num_devs || mdlist) {
+			mddev_ident_t mdident;
+			struct state *st;
+			mdu_array_info_t array;
+			char *dev;
+			int fd;
+			char *event = NULL;
+			int i;
+			char *event_disc = NULL;
+			if (num_devs) {
+				dev = devlist[dnum++];
+				mdident = conf_get_ident(config, dev);
+			} else {
+				mdident = mdlist;
+				dev = mdident->devname;
+				mdlist = mdlist->next;
+			}
+			for (st=statelist; st ; st=st->next)
+				if (strcmp(st->devname, dev)==0)
+					break;
+			if (!st) {
+				st =malloc(sizeof *st);
+				if (st == NULL)
+					continue;
+				st->devname = strdup(dev);
+				st->utime = 0;
+				st->next = statelist;
+				st->err = 0;
+				statelist = st;
+			}
+			fd = open(dev, O_RDONLY);
+			if (fd < 0) {
+				if (!st->err)
+					fprintf(stderr, Name ": cannot open %s: %s\n",
+						dev, strerror(errno));
+				st->err=1;
+				continue;
+			}
+			if (ioctl(fd, GET_ARRAY_INFO, &array)<0) {
+				if (!st->err)
+					fprintf(stderr, Name ": cannot get array info for %s: %s\n",
+						dev, strerror(errno));
+				st->err=1;
+				close(fd);
+				continue;
+			}
+			st->err = 0;
+		    
+			if (st->utime == array.utime &&
+			    st->failed == array.failed_disks) {
+				close(fd);
+				continue;
+			}
+			event = NULL;
+			if (st->utime) {
+				int i;
+				if (st->active > array.active_disks)
+					event = "Fail";
+				else if (st->working > array.working_disks)
+					event = "FailSpare";
+				else if (st->active < array.active_disks)
+					event = "ActiveSpare";
+			}
+			for (i=0; i<array.raid_disks+array.spare_disks; i++) {
+				mdu_disk_info_t disc;
+				disc.number = i;
+				if (ioctl(fd, GET_DISK_INFO, &disc)>= 0) {
+					if (event && event_disc == NULL &&
+					    st->devstate[i] != disc.state) {
+						char * dv = map_dev(disc.major, disc.minor);
+						if (dv)
+							event_disc = strdup(dv);
+					}
+					st->devstate[i] = disc.state;
+				}
+			}
+			close(fd);
+			st->active = array.active_disks;
+			st->working = array.working_disks;
+			st->spare = array.spare_disks;
+			st->failed = array.failed_disks;
+			st->utime = array.utime;
+			if (event)
+				alert(event, dev, event_disc, mailaddr, alert_cmd);
+		}
+		sleep(period);
+	}
+	return 0;
+}
+
+
+static void alert(char *event, char *dev, char *disc, char *mailaddr, char *cmd)
+{
+	if (cmd) {
+		int pid = fork();
+		switch(pid) {
+		default:
+			waitpid(pid, NULL, 0);
+			break;
+		case -1:
+			break;
+		case 0:
+			execl(cmd, cmd, event, dev, disc, NULL);
+			exit(2);
+		}
+	}
+	if (mailaddr && strncmp(event, "Fail", 4)==0) {
+		FILE *mp = popen(Sendmail, "w");
+		if (mp) {
+			char hname[256];
+			gethostname(hname, sizeof(hname));
+			signal(SIGPIPE, SIG_IGN);
+			fprintf(mp, "From: " Name " monitoring <root>\n");
+			fprintf(mp, "To: %s\n", mailaddr);
+			fprintf(mp, "Subject: %s event on %s:%s\n\n", event, dev, hname);
+
+			fprintf(mp, "This is an automatically generated mail message from " Name "\n");
+			fprintf(mp, "running on %s\n\n", hname);
+
+			fprintf(mp, "A %s event had been detected on md device %s.\n\n", event, dev);
+
+			if (disc)
+				fprintf(mp, "It could be related to sub-device %s.\n\n", disc);
+
+			fprintf(mp, "Faithfully yours, etc.\n");
+			fclose(mp);
+		}
+
+	}
+	/* FIXME log the event to syslog maybe */
+}