Warmboot Vlan neigh restore fix (sonic-net#1040)

* Send arp request after first Vlan member port is added

* Add wait logic after Vlan member add, nbrmgr to wait for restore complete

* Address comment to pass db as a parameter and open only once

cfgmgr/nbrmgr.cpp

@@ -47,7 +47,8 @@ NbrMgr::NbrMgr(DBConnector *cfgDb, DBConnector *appDb, DBConnector *stateDb, con
         m_statePortTable(stateDb, STATE_PORT_TABLE_NAME),
         m_stateLagTable(stateDb, STATE_LAG_TABLE_NAME),
         m_stateVlanTable(stateDb, STATE_VLAN_TABLE_NAME),
-        m_stateIntfTable(stateDb, STATE_INTERFACE_TABLE_NAME)
+        m_stateIntfTable(stateDb, STATE_INTERFACE_TABLE_NAME),
+        m_stateNeighRestoreTable(stateDb, STATE_NEIGH_RESTORE_TABLE_NAME)
 {
     int err = 0;
 
@@ -91,6 +92,19 @@ bool NbrMgr::isIntfStateOk(const string &alias)
     return false;
 }
 
+bool NbrMgr::isNeighRestoreDone()
+{
+    string value;
+
+    m_stateNeighRestoreTable.hget("Flags", "restored", value);
+    if (value == "true")
+    {
+        SWSS_LOG_INFO("Kernel neighbor table restore is done");
+        return true;
+    }
+    return false;
+}
+
 bool NbrMgr::setNeighbor(const string& alias, const IpAddress& ip, const MacAddress& mac)
 {
     SWSS_LOG_ENTER();

cfgmgr/nbrmgr.h

@@ -20,13 +20,15 @@ class NbrMgr : public Orch
     NbrMgr(DBConnector *cfgDb, DBConnector *appDb, DBConnector *stateDb, const vector<string> &tableNames);
     using Orch::doTask;
 
+    bool isNeighRestoreDone();
+
 private:
     bool isIntfStateOk(const string &alias);
     bool setNeighbor(const string& alias, const IpAddress& ip, const MacAddress& mac);
 
     void doTask(Consumer &consumer);
 
-    Table m_statePortTable, m_stateLagTable, m_stateVlanTable, m_stateIntfTable;
+    Table m_statePortTable, m_stateLagTable, m_stateVlanTable, m_stateIntfTable, m_stateNeighRestoreTable;
     struct nl_sock *m_nl_sock;
 };
 

cfgmgr/nbrmgrd.cpp

@@ -3,6 +3,7 @@
 #include <mutex>
 #include <fstream>
 #include <iostream>
+#include <chrono>
 
 #include "select.h"
 #include "exec.h"
@@ -12,6 +13,9 @@
 using namespace std;
 using namespace swss;
 
+#define RESTORE_NEIGH_WAIT_TIME_OUT 120
+#define RESTORE_NEIGH_WAIT_TIME_INT 10
+
 /* select() function timeout retry time, in millisecond */
 #define SELECT_TIMEOUT 1000
 
@@ -50,6 +54,21 @@ int main(int argc, char **argv)
 
         NbrMgr nbrmgr(&cfgDb, &appDb, &stateDb, cfg_nbr_tables);
 
+        chrono::steady_clock::time_point starttime = chrono::steady_clock::now();
+        while (!nbrmgr.isNeighRestoreDone())
+        {
+            chrono::duration<double> time_span = chrono::duration_cast<chrono::duration<double>>
+                                                 (chrono::steady_clock::now() - starttime);
+            int pasttime = int(time_span.count());
+            SWSS_LOG_INFO("Kernel neighbor table restoration waited for %d seconds", pasttime);
+            if (pasttime > RESTORE_NEIGH_WAIT_TIME_OUT)
+            {
+                SWSS_LOG_WARN("Kernel neighbor table restore is not finished!");
+                break;
+            }
+            sleep(RESTORE_NEIGH_WAIT_TIME_INT);
+        }
+
         std::vector<Orch *> cfgOrchList = {&nbrmgr};
 
         swss::Select s;

neighsyncd/restore_neighbors.py

@@ -25,11 +25,29 @@
 from scapy.all import conf, in6_getnsma, inet_pton, inet_ntop, in6_getnsmac, get_if_hwaddr, Ether, ARP, IPv6, ICMPv6ND_NS, ICMPv6NDOptSrcLLAddr
 from swsscommon import swsscommon
 import errno
+import syslog
 
 logger = logging.getLogger(__name__)
 logger.setLevel(logging.WARNING)
 logger.addHandler(logging.NullHandler())
 
+SYSLOG_IDENTIFIER = 'restore_neighbor'
+
+def log_info(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_INFO, msg)
+    syslog.closelog()
+
+def log_warning(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_WARNING, msg)
+    syslog.closelog()
+
+def log_error(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_ERR, msg)
+    syslog.closelog()
+
 # timeout the restore process in 110 seconds if not finished
 # This is mostly to wait for interfaces to be created and up after system warm-reboot
 # and this process is started by supervisord in swss docker.
@@ -58,12 +76,27 @@ def is_intf_oper_state_up(intf):
         state_file = open(oper_file.format(intf), 'r')
         state = state_file.readline().rstrip()
     except Exception as e:
-        logger.info('Error: {}'.format(str(e)))
+        log_info('Error: {}'.format(str(e)))
         return False
     if state == '1':
         return True
     return False
 
+def is_intf_up(intf, db):
+    if not is_intf_oper_state_up(intf):
+         return False
+    if 'Vlan' in intf:
+        table_name = 'VLAN_MEMBER_TABLE|{}|*'.format(intf)
+        key = db.keys(db.STATE_DB, table_name)
+        if key is None:
+            log_info ("Vlan member is not yet created")
+            return False
+        if is_intf_up.counter == 0:
+            time.sleep(3*CHECK_INTERVAL)
+            is_intf_up.counter = 1
+        log_info ("intf {} is up".format(intf))
+    return True
+
 # read the neigh table from AppDB to memory, format as below
 # build map as below, this can efficiently access intf and family groups later
 #       { intf1 -> { { family1 -> [[ip1, mac1], [ip2, mac2] ...] }
@@ -131,7 +164,7 @@ def read_neigh_table_to_maps():
 
 # Use netlink to set neigh table into kernel, not overwrite the existing ones
 def set_neigh_in_kernel(ipclass, family, intf_idx, dst_ip, dmac):
-    logging.info('Add neighbor entries: family: {}, intf_idx: {}, ip: {}, mac: {}'.format(
+    log_info('Add neighbor entries: family: {}, intf_idx: {}, ip: {}, mac: {}'.format(
     family, intf_idx, dst_ip, dmac))
 
     if family not in ip_family:
@@ -152,7 +185,7 @@ def set_neigh_in_kernel(ipclass, family, intf_idx, dst_ip, dmac):
     # If neigh exists, log it but no exception raise, other exceptions, raise
     except NetlinkError as e:
         if e[0] == errno.EEXIST:
-            logger.warning('Neigh exists in kernel with family: {}, intf_idx: {}, ip: {}, mac: {}'.format(
+            log_warning('Neigh exists in kernel with family: {}, intf_idx: {}, ip: {}, mac: {}'.format(
             family, intf_idx, dst_ip, dmac))
         else:
             raise
@@ -196,10 +229,13 @@ def restore_update_kernel_neighbors(intf_neigh_map, timeout=DEF_TIME_OUT):
     ipclass = IPRoute()
     mtime = monotonic.time.time
     start_time = mtime()
+    is_intf_up.counter = 0
+    db = swsssdk.SonicV2Connector(host='127.0.0.1')
+    db.connect(db.STATE_DB, False)
     while (mtime() - start_time) < timeout:
         for intf, family_neigh_map in intf_neigh_map.items():
             # only try to restore to kernel when link is up
-            if is_intf_oper_state_up(intf):
+            if is_intf_up(intf, db):
                 src_mac = get_if_hwaddr(intf)
                 intf_idx = ipclass.link_lookup(ifname=intf)[0]
                 # create socket per intf to send packets
@@ -215,6 +251,8 @@ def restore_update_kernel_neighbors(intf_neigh_map, timeout=DEF_TIME_OUT):
                             # use netlink to set neighbor entries
                             set_neigh_in_kernel(ipclass, family, intf_idx, dst_ip, dmac)
 
+                            log_info('Sending Neigh with family: {}, intf_idx: {}, ip: {}, mac: {}'.format(
+                            family, intf_idx, dst_ip, dmac))
                             # sending arp/ns packet to update kernel neigh info
                             s.send(build_arp_ns_pkt(family, src_mac, src_ip, dst_ip))
                         # delete this family on the intf
@@ -229,28 +267,27 @@ def restore_update_kernel_neighbors(intf_neigh_map, timeout=DEF_TIME_OUT):
         if not intf_neigh_map:
             break
         time.sleep(CHECK_INTERVAL)
+    db.close(db.STATE_DB)
 
 
 def main():
 
-    print "restore_neighbors service is started"
-
+    log_info ("restore_neighbors service is started")
     # Use warmstart python binding to check warmstart information
     warmstart = swsscommon.WarmStart()
     warmstart.initialize("neighsyncd", "swss")
     warmstart.checkWarmStart("neighsyncd", "swss", False)
 
     # if swss or system warm reboot not enabled, don't run
     if not warmstart.isWarmStart():
-        print "restore_neighbors service is skipped as warm restart not enabled"
+        log_info ("restore_neighbors service is skipped as warm restart not enabled")
         return
 
     # swss restart not system warm reboot, set statedb directly
     if not warmstart.isSystemWarmRebootEnabled():
         set_statedb_neigh_restore_done()
-        print "restore_neighbors service is done as system warm reboot not enabled"
+        log_info ("restore_neighbors service is done as system warm reboot not enabled")
         return
-
     # read the neigh table from appDB to internal map
     try:
         intf_neigh_map = read_neigh_table_to_maps()
@@ -266,7 +303,7 @@ def main():
 
     # set statedb to signal other processes like neighsyncd
     set_statedb_neigh_restore_done()
-    print "restore_neighbor service is done for system warmreboot"
+    log_info ("restore_neighbor service is done for system warmreboot")
     return
 
 if __name__ == '__main__':