Fix: cib: Increased paranoia when peer updates fail to apply in compa…

…tability mode

This is caused by either:
- fingerprint mismatches between the actual and expected results, or
- attrd (the new one) doing some local writes which bumped the local
  version past the DC's (which is running the old cib).

Solution is to grab a new copy from the DC each time.

cib/messages.c

@@ -369,6 +369,7 @@ cib_server_process_diff(const char *op, int options, const char *section, xmlNod
     }
 
     rc = cib_process_diff(op, options, section, req, input, existing_cib, result_cib, answer);
+    crm_trace("result: %s (%d), %s", pcmk_strerror(rc), rc, cib_is_master?"master":"slave");
 
     if (rc == -pcmk_err_diff_resync && cib_is_master == FALSE) {
         free_xml(*result_cib);
@@ -380,6 +381,13 @@ cib_server_process_diff(const char *op, int options, const char *section, xmlNod
         if (options & cib_force_diff) {
             crm_warn("Not requesting full refresh in R/W mode");
         }
+
+    } else if(rc != pcmk_ok && cib_legacy_mode()) {
+        crm_warn("Something went wrong in compatibility mode, requesting full refresh");
+        xml_log_patchset(LOG_INFO, __FUNCTION__, input);
+        free_xml(*result_cib);
+        *result_cib = NULL;
+        send_sync_request(NULL);
     }
 
     return rc;