diff --git a/Makefile.am b/Makefile.am
index 42a09f2..43407cc 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -24,6 +24,7 @@ glorytun_SOURCES = \
     src/set.c \
     src/show.c \
     src/str.h \
+    src/sync.c \
     src/tun.c \
     src/tun.h
 
diff --git a/README.md b/README.md
index 72faf4e..de67053 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,7 @@ available commands:
   bench    start a crypto bench
   bind     start a new tunnel
   set      change tunnel properties
+  sync     re-sync tunnels
   keygen   generate a new secret key
   path     manage paths
   version  show version
diff --git a/meson.build b/meson.build
index c8ded67..5b8c867 100644
--- a/meson.build
+++ b/meson.build
@@ -33,6 +33,7 @@ executable('glorytun', install: true,
     'src/path.c',
     'src/set.c',
     'src/show.c',
+    'src/sync.c',
     'src/tun.c',
   ],
   dependencies: [
diff --git a/src/bind.c b/src/bind.c
index e83afd8..07343a3 100644
--- a/src/bind.c
+++ b/src/bind.c
@@ -289,6 +289,10 @@ gt_bind(int argc, char **argv)
                     res.status.bind = bind_addr;
                     res.status.peer = peer_addr;
                     break;
+                case CTL_SYNC:
+                    if (mud_send(mud, NULL, 0, 0) == -1)
+                        res.ret = errno;
+                    break;
                 }
                 if (sendto(ctl_fd, &res, sizeof(res), 0,
                            (const struct sockaddr *)&ss, sl) == -1)
diff --git a/src/common.h b/src/common.h
index 25b4b33..b8ac74e 100644
--- a/src/common.h
+++ b/src/common.h
@@ -74,3 +74,4 @@ int gt_path   (int, char **);
 int gt_keygen (int, char **);
 int gt_bench  (int, char **);
 int gt_set    (int, char **);
+int gt_sync   (int, char **);
diff --git a/src/ctl.h b/src/ctl.h
index 2a432e9..e1fa658 100644
--- a/src/ctl.h
+++ b/src/ctl.h
@@ -14,6 +14,7 @@ enum ctl_type {
     CTL_TIMEOUT,
     CTL_TIMETOLERANCE,
     CTL_PATH_STATUS,
+    CTL_SYNC,
 };
 
 struct ctl_msg {
diff --git a/src/main.c b/src/main.c
index 8209514..e947601 100644
--- a/src/main.c
+++ b/src/main.c
@@ -64,6 +64,7 @@ main(int argc, char **argv)
         {"bench", "start a crypto bench", gt_bench},
         {"bind", "start a new tunnel", gt_bind},
         {"set", "change tunnel properties", gt_set},
+        {"sync", "re-sync tunnels", gt_sync},
         {"keygen", "generate a new secret key", gt_keygen},
         {"path", "manage paths", gt_path},
         {"version", "show version", gt_version},
diff --git a/src/sync.c b/src/sync.c
new file mode 100644
index 0000000..fe931cc
--- /dev/null
+++ b/src/sync.c
@@ -0,0 +1,71 @@
+#include "common.h"
+#include "ctl.h"
+#include "str.h"
+
+#include "../argz/argz.h"
+
+#include <stdio.h>
+#include <dirent.h>
+
+static int
+gt_sync_dev(const char *dev)
+{
+    const int fd = ctl_connect(GT_RUNDIR, dev);
+
+    if (fd < 0) {
+        if (fd == -1)
+            perror("sync");
+        return 1;
+    }
+
+    struct ctl_msg res, req = {
+        .type = CTL_SYNC,
+    };
+
+    const int ret = ctl_reply(fd, &res, &req);
+
+    if (ret == -1)
+        perror("sync");
+
+    ctl_delete(fd);
+
+    return ret;
+}
+
+int
+gt_sync(int argc, char **argv)
+{
+    const char *dev = NULL;
+
+    struct argz syncz[] = {
+        {"dev", "NAME", &dev, argz_str},
+        {NULL}};
+
+    if (argz(syncz, argc, argv))
+        return 1;
+
+    if (dev) {
+        gt_sync_dev(dev);
+        return 0;
+    }
+
+    DIR *dp = opendir(GT_RUNDIR);
+
+    if (!dp) {
+        if (errno == ENOENT)
+            return 0;
+        perror("sync");
+        return 1;
+    }
+
+    struct dirent *d = NULL;
+
+    while (d = readdir(dp), d) {
+        if (d->d_name[0] != '.')
+            gt_sync_dev(d->d_name);
+    }
+
+    closedir(dp);
+
+    return 0;
+}