rgw: require --yes-i-really-mean-it to promote zone with stale metadata

if a zone is promoted to master before it has a chance to sync from the
previous master zone, any metadata entries after its sync position will
be lost

print an error if 'period commit' is trying to promote a zone that is
more than one period behind the current master, and only allow the
commit to proceed if the --yes-i-really-mean-it flag is provided

Signed-off-by: Casey Bodley <cbodley@redhat.com>

diff --git a/src/rgw/rgw_admin.cc b/src/rgw/rgw_admin.cc
index 4601055c9f02507a309465d3cd9ecafa6c8ffbbe..41ef12ef06f77380011f7d78f9a6a4e18f12d2d2 100644 (file)
--- a/src/rgw/rgw_admin.cc
+++ b/src/rgw/rgw_admin.cc
@@ -1587,7 +1587,8 @@ static int send_to_remote_or_url(const string& remote, const string& url,
 
 static int commit_period(RGWRealm& realm, RGWPeriod& period,
                          string remote, const string& url,
-                         const string& access, const string& secret)
+                         const string& access, const string& secret,
+                         bool force)
 {
   const string& master_zone = period.get_master_zone();
   if (master_zone.empty()) {
@@ -1605,7 +1606,7 @@ static int commit_period(RGWRealm& realm, RGWPeriod& period,
       return ret;
     }
     // the master zone can commit locally
-    ret = period.commit(realm, current_period, cerr);
+    ret = period.commit(realm, current_period, cerr, force);
     if (ret < 0) {
       cerr << "failed to commit period: " << cpp_strerror(-ret) << std::endl;
     }
@@ -1682,7 +1683,7 @@ static int update_period(const string& realm_id, const string& realm_name,
                          const string& period_id, const string& period_epoch,
                          bool commit, const string& remote, const string& url,
                          const string& access, const string& secret,
-                         Formatter *formatter)
+                         Formatter *formatter, bool force)
 {
   RGWRealm realm(realm_id, realm_name);
   int ret = realm.init(g_ceph_context, store);
@@ -1713,7 +1714,7 @@ static int update_period(const string& realm_id, const string& realm_name,
     return ret;
   }
   if (commit) {
-    ret = commit_period(realm, period, remote, url, access, secret);
+    ret = commit_period(realm, period, remote, url, access, secret, force);
     if (ret < 0) {
       cerr << "failed to commit period: " << cpp_strerror(-ret) << std::endl;
       return ret;
@@ -3039,7 +3040,7 @@ int main(int argc, const char **argv)
       {
         int ret = update_period(realm_id, realm_name, period_id, period_epoch,
                                 commit, remote, url, access_key, secret_key,
-                                formatter);
+                                formatter, yes_i_really_mean_it);
        if (ret < 0) {
          return -ret;
        }
@@ -4576,7 +4577,7 @@ int main(int argc, const char **argv)
     {
       int ret = update_period(realm_id, realm_name, period_id, period_epoch,
                               commit, remote, url, access_key, secret_key,
-                              formatter);
+                              formatter, yes_i_really_mean_it);
       if (ret < 0) {
        return -ret;
       }
@@ -4597,7 +4598,8 @@ int main(int argc, const char **argv)
         cerr << "period init failed: " << cpp_strerror(-ret) << std::endl;
         return -ret;
       }
-      ret = commit_period(realm, period, remote, url, access_key, secret_key);
+      ret = commit_period(realm, period, remote, url, access_key, secret_key,
+                          yes_i_really_mean_it);
       if (ret < 0) {
         cerr << "failed to commit period: " << cpp_strerror(-ret) << std::endl;
         return -ret;

diff --git a/src/rgw/rgw_rados.cc b/src/rgw/rgw_rados.cc
index 74673a009ec5914e68f14ff913c3d64c0d3c6399..329e09589acc645cc6f5c4658b83598c935bbaa3 100644 (file)
--- a/src/rgw/rgw_rados.cc
+++ b/src/rgw/rgw_rados.cc
@@ -1441,7 +1441,9 @@ static int read_sync_status(RGWRados *store, rgw_meta_sync_status *sync_status)
   return r;
 }
 
-int RGWPeriod::update_sync_status(const RGWPeriod &current_period)
+int RGWPeriod::update_sync_status(const RGWPeriod &current_period,
+                                  std::ostream& error_stream,
+                                  bool force_if_stale)
 {
   rgw_meta_sync_status status;
   int r = read_sync_status(store, &status);
@@ -1458,9 +1460,20 @@ int RGWPeriod::update_sync_status(const RGWPeriod &current_period)
     // no sync status markers for the current period
     assert(current_epoch > status.sync_info.realm_epoch);
     const int behind = current_epoch - status.sync_info.realm_epoch;
-    lderr(cct) << "ERROR: This zone is " << behind << " period(s) behind "
-          "the current master zone in metadata sync." << dendl;
-    return -EINVAL;
+    if (!force_if_stale && current_epoch > 1) {
+      error_stream << "ERROR: This zone is " << behind << " period(s) behind "
+          "the current master zone in metadata sync. If this zone is promoted "
+          "to master, any metadata changes during that time are likely to "
+          "be lost.\n"
+          "Waiting for this zone to catch up on metadata sync (see "
+          "'radosgw-admin sync status') is recommended.\n"
+          "To promote this zone to master anyway, add the flag "
+          "--yes-i-really-mean-it." << std::endl;
+      return -EINVAL;
+    }
+    // empty sync status markers - other zones will skip this period during
+    // incremental metadata sync
+    markers.resize(status.sync_info.num_shards);
   } else {
     markers.reserve(status.sync_info.num_shards);
     for (auto& i : status.sync_markers) {
@@ -1478,7 +1491,7 @@ int RGWPeriod::update_sync_status(const RGWPeriod &current_period)
 }
 
 int RGWPeriod::commit(RGWRealm& realm, const RGWPeriod& current_period,
-                      std::ostream& error_stream)
+                      std::ostream& error_stream, bool force_if_stale)
 {
   ldout(cct, 20) << __func__ << " realm " << realm.get_id() << " period " << current_period.get_id() << dendl;
   // gateway must be in the master zone to commit
@@ -1508,7 +1521,7 @@ int RGWPeriod::commit(RGWRealm& realm, const RGWPeriod& current_period,
   // did the master zone change?
   if (master_zone != current_period.get_master_zone()) {
     // store the current metadata sync status in the period
-    int r = update_sync_status(current_period);
+    int r = update_sync_status(current_period, error_stream, force_if_stale);
     if (r < 0) {
       ldout(cct, 0) << "failed to update metadata sync status: "
           << cpp_strerror(-r) << dendl;

diff --git a/src/rgw/rgw_rados.h b/src/rgw/rgw_rados.h
index e0ad2175355ed0fa28f8814f8071a8c2b254acd3..c42256639d72973e1e6f45550aa6911c8f741181 100644 (file)
--- a/src/rgw/rgw_rados.h
+++ b/src/rgw/rgw_rados.h
@@ -1787,7 +1787,8 @@ class RGWPeriod
   const string get_period_oid_prefix();
 
   // gather the metadata sync status for each shard; only for use on master zone
-  int update_sync_status(const RGWPeriod &current_period);
+  int update_sync_status(const RGWPeriod &current_period,
+                         std::ostream& error_stream, bool force_if_stale);
 
 public:
   RGWPeriod() : epoch(0), cct(NULL), store(NULL) {}
@@ -1860,7 +1861,7 @@ public:
 
   // commit a staging period; only for use on master zone
   int commit(RGWRealm& realm, const RGWPeriod &current_period,
-             std::ostream& error_stream);
+             std::ostream& error_stream, bool force_if_stale = false);
 
   void encode(bufferlist& bl) const {
     ENCODE_START(1, 1, bl);