Add 'zpool status -e' flag to see unhealthy vdevs

When very large pools are present, it can be laborious to find
reasons for why a pool is degraded and/or where an unhealthy vdev
is. This option filters out vdevs that are ONLINE and with no errors
to make it easier to see where the issues are. Root and parents of
unhealthy vdevs will always be printed.

Testing:
ZFS errors and drive failures for multiple vdevs were simulated with
zinject.

Sample vdev listings with '-e' option
- All vdevs healthy
    NAME        STATE     READ WRITE CKSUM
    iron5       ONLINE       0     0     0

- ZFS errors
    NAME        STATE     READ WRITE CKSUM
    iron5       ONLINE       0     0     0
      raidz2-5  ONLINE       1     0     0
        L23     ONLINE       1     0     0
        L24     ONLINE       1     0     0
        L37     ONLINE       1     0     0

- Vdev faulted
    NAME        STATE     READ WRITE CKSUM
    iron5       DEGRADED     0     0     0
      raidz2-6  DEGRADED     0     0     0
        L67     FAULTED      0     0     0  too many errors

- Vdev faults and data errors
    NAME        STATE     READ WRITE CKSUM
    iron5       DEGRADED     0     0     0
      raidz2-1  DEGRADED     0     0     0
        L2      FAULTED      0     0     0  too many errors
      raidz2-5  ONLINE       1     0     0
        L23     ONLINE       1     0     0
        L24     ONLINE       1     0     0
        L37     ONLINE       1     0     0
      raidz2-6  DEGRADED     0     0     0
        L67     FAULTED      0     0     0  too many errors

- Vdev missing
    NAME        STATE     READ WRITE CKSUM
    iron5       DEGRADED     0     0     0
      raidz2-6  DEGRADED     0     0     0
        L67     UNAVAIL      3     1     0

- Slow devices when -s provided with -e
    NAME        STATE     READ WRITE CKSUM  SLOW
    iron5       DEGRADED     0     0     0     -
      raidz2-5  DEGRADED     0     0     0     -
        L10     FAULTED      0     0     0     0  external device fault
        L51     ONLINE       0     0     0    14

Signed-off-by: Cameron Harr <[email protected]>

Author: cmharr

cmd/zpool/zpool_main.c

@@ -2161,6 +2161,7 @@ typedef struct status_cbdata {
 	boolean_t	cb_explain;
 	boolean_t	cb_first;
 	boolean_t	cb_dedup_stats;
+	boolean_t	cb_print_unhealthy;
 	boolean_t	cb_print_status;
 	boolean_t	cb_print_slow_ios;
 	boolean_t	cb_print_vdev_init;
@@ -2357,6 +2358,35 @@ health_str_to_color(const char *health)
 	return (NULL);
 }
 
+/*
+ * Called for each leaf vdev.  Returns 0 if the vdev is healthy.
+ * A vdev is unhealthy if any of the following are true:
+ * 1) there are read, write, or checksum errors,
+ * 2) its state is not ONLINE, or
+ * 3) slow IO reporting was requested (-s) and there are slow IOs.
+ */
+static int
+vdev_is_healthy(void *hdl_data, nvlist_t *nv, void *data)
+{
+	status_cbdata_t *cb = data;
+	vdev_stat_t *vs;
+	uint_t vsc;
+	(void) hdl_data;
+
+	if (nvlist_lookup_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS,
+	    (uint64_t **)&vs, &vsc) != 0)
+		return (1);
+
+	if (vs->vs_checksum_errors || vs->vs_read_errors ||
+	    vs->vs_write_errors || vs->vs_state != VDEV_STATE_HEALTHY)
+		return (1);
+
+	if (cb->cb_print_slow_ios && vs->vs_slow_ios)
+		return (1);
+
+	return (0);
+}
+
 /*
  * Print out configuration state as requested by status_callback.
  */
@@ -2375,7 +2405,8 @@ print_status_config(zpool_handle_t *zhp, status_cbdata_t *cb, const char *name,
 	const char *state;
 	const char *type;
 	const char *path = NULL;
-	const char *rcolor = NULL, *wcolor = NULL, *ccolor = NULL;
+	const char *rcolor = NULL, *wcolor = NULL, *ccolor = NULL,
+	    *scolor = NULL;
 
 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
 	    &child, &children) != 0)
@@ -2402,6 +2433,15 @@ print_status_config(zpool_handle_t *zhp, status_cbdata_t *cb, const char *name,
 			state = gettext("AVAIL");
 	}
 
+	/*
+	 * If '-e' is specified then top-level vdevs and their children
+	 * can be pruned if all of their leaves are healthy.
+	 */
+	if (cb->cb_print_unhealthy && depth > 0 &&
+	    for_each_vdev_in_nvlist(nv, vdev_is_healthy, cb) == 0) {
+		return;
+	}
+
 	printf_color(health_str_to_color(state),
 	    "\t%*s%-*s  %-8s", depth, "", cb->cb_namewidth - depth,
 	    name, state);
@@ -2416,6 +2456,9 @@ print_status_config(zpool_handle_t *zhp, status_cbdata_t *cb, const char *name,
 		if (vs->vs_checksum_errors)
 			ccolor = ANSI_RED;
 
+		if (vs->vs_slow_ios)
+			scolor = ANSI_BLUE;
+
 		if (cb->cb_literal) {
 			fputc(' ', stdout);
 			printf_color(rcolor, "%5llu",
@@ -2448,9 +2491,10 @@ print_status_config(zpool_handle_t *zhp, status_cbdata_t *cb, const char *name,
 			}
 
 			if (cb->cb_literal)
-				printf(" %5llu", (u_longlong_t)vs->vs_slow_ios);
+				printf_color(scolor, " %5llu",
+				    (u_longlong_t)vs->vs_slow_ios);
 			else
-				printf(" %5s", rbuf);
+				printf_color(scolor, " %5s", rbuf);
 		}
 		if (cb->cb_print_power) {
 			if (children == 0)  {
@@ -9106,9 +9150,11 @@ status_callback(zpool_handle_t *zhp, void *data)
 				(void) printf(gettext(
 				    "errors: No known data errors\n"));
 			} else if (!cbp->cb_verbose) {
+				color_start(ANSI_RED);
 				(void) printf(gettext("errors: %llu data "
 				    "errors, use '-v' for a list\n"),
 				    (u_longlong_t)nerr);
+				color_end();
 			} else {
 				print_error_log(zhp);
 			}
@@ -9129,6 +9175,7 @@ status_callback(zpool_handle_t *zhp, void *data)
  *              [pool] [interval [count]]
  *
  *	-c CMD	For each vdev, run command CMD
+ *	-e	Display only unhealthy vdevs
  *	-i	Display vdev initialization status.
  *	-g	Display guid for individual vdev name.
  *	-L	Follow links when resolving vdev path name.
@@ -9160,7 +9207,7 @@ zpool_do_status(int argc, char **argv)
 	};
 
 	/* check options */
-	while ((c = getopt_long(argc, argv, "c:igLpPsvxDtT:", long_options,
+	while ((c = getopt_long(argc, argv, "c:eigLpPsvxDtT:", long_options,
 	    NULL)) != -1) {
 		switch (c) {
 		case 'c':
@@ -9187,6 +9234,9 @@ zpool_do_status(int argc, char **argv)
 			}
 			cmd = optarg;
 			break;
+		case 'e':
+			cb.cb_print_unhealthy = B_TRUE;
+			break;
 		case 'i':
 			cb.cb_print_vdev_init = B_TRUE;
 			break;

man/man8/zpool-status.8

@@ -36,7 +36,7 @@
 .Sh SYNOPSIS
 .Nm zpool
 .Cm status
-.Op Fl DigLpPstvx
+.Op Fl DeigLpPstvx
 .Op Fl T Sy u Ns | Ns Sy d
 .Op Fl c Op Ar SCRIPT1 Ns Oo , Ns Ar SCRIPT2 Oc Ns …
 .Oo Ar pool Oc Ns …
@@ -69,6 +69,8 @@ See the
 option of
 .Nm zpool Cm iostat
 for complete details.
+.It Fl e
+Only show unhealthy vdevs (not-ONLINE or with errors).
 .It Fl i
 Display vdev initialization status.
 .It Fl g