+ * zpool split [-n] [-o prop=val] ...
+ * [-o mntopt] ...
+ * [-R altroot] <pool> <newpool> [<device> ...]
+ *
+ * -n Do not split the pool, but display the resulting layout if
+ * it were to be split.
+ * -o Set property=value, or set mount options.
+ * -R Mount the split-off pool under an alternate root.
+ *
+ * Splits the named pool and gives it the new pool name. Devices to be split
+ * off may be listed, provided that no more than one device is specified
+ * per top-level vdev mirror. The newly split pool is left in an exported
+ * state unless -R is specified.
+ *
+ * Restrictions: the top-level of the pool pool must only be made up of
+ * mirrors; all devices in the pool must be healthy; no device may be
+ * undergoing a resilvering operation.
+ */
+int
+zpool_do_split(int argc, char **argv)
+{
+ char *srcpool, *newpool, *propval;
+ char *mntopts = NULL;
+ splitflags_t flags;
+ int c, ret = 0;
+ zpool_handle_t *zhp;
+ nvlist_t *config, *props = NULL;
+
+ flags.dryrun = B_FALSE;
+ flags.import = B_FALSE;
+
+ /* check options */
+ while ((c = getopt(argc, argv, ":R:no:")) != -1) {
+ switch (c) {
+ case 'R':
+ flags.import = B_TRUE;
+ if (add_prop_list(
+ zpool_prop_to_name(ZPOOL_PROP_ALTROOT), optarg,
+ &props, B_TRUE) != 0) {
+ if (props)
+ nvlist_free(props);
+ usage(B_FALSE);
+ }
+ break;
+ case 'n':
+ flags.dryrun = B_TRUE;
+ break;
+ case 'o':
+ if ((propval = strchr(optarg, '=')) != NULL) {
+ *propval = '\0';
+ propval++;
+ if (add_prop_list(optarg, propval,
+ &props, B_TRUE) != 0) {
+ if (props)
+ nvlist_free(props);
+ usage(B_FALSE);
+ }
+ } else {
+ mntopts = optarg;
+ }
+ break;
+ case ':':
+ (void) fprintf(stderr, gettext("missing argument for "
+ "'%c' option\n"), optopt);
+ usage(B_FALSE);
+ break;
+ case '?':
+ (void) fprintf(stderr, gettext("invalid option '%c'\n"),
+ optopt);
+ usage(B_FALSE);
+ break;
+ }
+ }
+
+ if (!flags.import && mntopts != NULL) {
+ (void) fprintf(stderr, gettext("setting mntopts is only "
+ "valid when importing the pool\n"));
+ usage(B_FALSE);
+ }
+
+ argc -= optind;
+ argv += optind;
+
+ if (argc < 1) {
+ (void) fprintf(stderr, gettext("Missing pool name\n"));
+ usage(B_FALSE);
+ }
+ if (argc < 2) {
+ (void) fprintf(stderr, gettext("Missing new pool name\n"));
+ usage(B_FALSE);
+ }
+
+ srcpool = argv[0];
+ newpool = argv[1];
+
+ argc -= 2;
+ argv += 2;
+
+ if ((zhp = zpool_open(g_zfs, srcpool)) == NULL)
+ return (1);
+
+ config = split_mirror_vdev(zhp, newpool, props, flags, argc, argv);
+ if (config == NULL) {
+ ret = 1;
+ } else {
+ if (flags.dryrun) {
+ (void) printf(gettext("would create '%s' with the "
+ "following layout:\n\n"), newpool);
+ print_vdev_tree(NULL, newpool, config, 0, B_FALSE);
+ }
+ nvlist_free(config);
+ }
+
+ zpool_close(zhp);
+
+ if (ret != 0 || flags.dryrun || !flags.import)
+ return (ret);
+
+ /*
+ * The split was successful. Now we need to open the new
+ * pool and import it.
+ */
+ if ((zhp = zpool_open_canfail(g_zfs, newpool)) == NULL)
+ return (1);
+ if (zpool_get_state(zhp) != POOL_STATE_UNAVAIL &&
+ zpool_enable_datasets(zhp, mntopts, 0) != 0) {
+ ret = 1;
+ (void) fprintf(stderr, gettext("Split was succssful, but "
+ "the datasets could not all be mounted\n"));
+ (void) fprintf(stderr, gettext("Try doing '%s' with a "
+ "different altroot\n"), "zpool import");
+ }
+ zpool_close(zhp);
+
+ return (ret);
+}
+
+
+
+/*