ISSU MPLS Clients

MPLS applications can be upgraded using the In Service Software Upgrade (ISSU) process and the enhanced Fast Software Upgrade (eFSU) process. Thus, MPLS applications are considered ISSU’s MPLS clients. The ISSU process allows Cisco IOS software at the router level to be updated or otherwise modified while packet forwarding continues. At the line-card level , the eFSU process minimizes line-card downtime during such upgrades to between 30 and 90 seconds, by loading the new line-card image before the ISSU switchover occurs from the active to the standby Route Processor (RP).

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for ISSU MPLS Clients

Before you perform an upgrade, you need to verify that the clients you are concerned about are compatible with the intended switchover. Use the commands listed in the Verifying the ISSU Process for an MPLS Client to determine compatibility.

The success performance of some clients in the upgraded network will depend upon their compatibility with other clients as described in the table below.

Table 1 MPLS Client Interdependencies

This client . . .

...can only work when this client is shown to be compatible

MPLS VPN

LSD Label Manager High Availability

LDP

LSD Label Manager High Availability

VRF (“Table ID”)

LSD Label Manager High Availability

LSD Label Manager High Availability

Base clients: Checkpointing and Redundancy Facility

MFI Pull

XDR

MFI Push

XDR

LSPV Push within OAM

XDR

TE

Base clients:

  • Checkpointing and Redundancy Facility
  • MPLS TE High Availability

Restrictions for ISSU MPLS Clients

Because line cards in the Cisco series 7600 routers do not support Minimum Disruption Restart (MDR), they reset when eFSU is performed. That causes IGP adjacencies to flap (adjacent routes are advertised as unavailable and then available again in quick sequence), bringing down the MPLS traffic engineering (TE) tunnels. Therefore, after an eFSU operation, it may take as long as two minutes for TE tunnels to be resignaled and reestablished.

For this reason, we recommend that before you begin eFSU you first disable Resource Reservation Protocol Graceful Restart (RSVP GR) full mode. If this mode is not disabled, RSVP can inadvertently delay the reestablishment of TE tunnels while it waits for the recovery of the preexisting TE tunnel state.

To see how long each line card will be placed out of service during the eFSU process, use the show issu outage slot all command as described in the Determining Impending Line-Card Outage Periods During an ISSU.

Information About ISSU MPLS Clients

This section provides information about upgrading MPLS-related applications through ISSU and eFSU. Those MPLS applications are considered ISSU’s MPLS “clients.”

For information on the entire ISSU and eFSU procedure, please see the document, Cisco IOS In Service Software Upgrade and Enhanced Fast Software Upgrade Process.

For information specific to eFSU on the Cisco 7600 series router, please refer to the “ISSU and eFSU on Cisco 7600 Series Routers” chapter in the Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SR.

ISSU-Capable Protocols and Applications Clients

Protocols and applications that can be upgraded through the ISSU process are considered clients of ISSU. These include at least the following:

  • Address Resolution Protocol (ARP)
  • Asynchronous Transfer Mode (ATM)
  • Cisco Express Forwarding
  • Dynamic Host Configuration Protocol (DHCP)
  • EtherChannel—port aggregration protocol (PagP) and Link Aggregration Control Protocol (LACP)
  • Frame Relay (FR)
  • Gateway Load Balancing Protocol (GLBP)
  • High-Level Data Link Control (HDLC)
  • Hot Standby Router Protocol (HSRP)
  • IEEE 802.1x and 802.3af
  • Internet Group Management Protocol (IGMP) snooping
  • IP host
  • Intermediate System-to-Intermediate System (IS-IS)
  • Multiprotocol Label Switching (MPLS)
  • PPP and Multilink PPP
  • Port security
  • Quality of service (QoS)
  • Remote File System (RFS) versioning
  • Simple Network Management Protocol (SNMP)
  • Spanning Tree Protocol (STP)

ISSU-Capable MPLS Feature Sets

Within the MPLS technology, ISSU supports the following feature sets as clients:

  • Label Distribution Protocol (LDP)
  • MPLS Virtual Private Network (MPLS VPN)
  • VPN routing and forwarding (VRF), also called the “Table ID” client
  • Label Switching Database Label Manager for high availability, usually called “LSD Label Manager for HA”
  • MPLS Forwarding Infrastructure Pull, called “MFI Pull”
  • MPLS Forwarding Infrastructure Push, called “MFI Push”

Beginning with Cisco IOS Release 12.2(33)SRB1, the following MPLS features are also supported as ISSU clients:

  • Label Switched Path Verification Push within Operation, Administration, and Management (OAM), called “LSPV Push”
  • TE

How to Verify that an MPLS Client Can Support an In Service Software Upgrade

Determining Impending Line-Card Outage Periods During an ISSU

Perform this task to determining impending line-card outage periods during an ISSU.

During an ISSU, the router preloads line-card software onto line cards that support enhanced Fast Service Upgrade (eFSU). Then, when the switchover occurs between active and standby processors, the line cards that support eFSU are restarted with the new, preloaded software, which helps to minimize outage time during the upgrade. Line cards that do not support eFSU undergo a hard reset at switchover, and the software image is loaded after the line card is restarted.


Note


For the complete task sequence that accomplishes ISSU and eFSU, please see the document entitled, Cisco IOS In Service Software Upgrade and Enhanced Fast Software Upgrade Process.


Before You Begin

Ensure that you have successfully loaded new Cisco IOS software onto the standby processor as described in Cisco IOS In Service Software Upgrade and Enhanced Fast Software Upgrade Process.

SUMMARY STEPS

    1.    enable

    2.    show issu outage slot all


DETAILED STEPS
      Command or Action Purpose
    Step 1 enable


    Example:
    Router> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.
     
    Step 2 show issu outage slot all


    Example:
    Router# show issu outage slot all


    Example:
     
               
     

    Determines the maximum length of time each line card could be down when use of the issu runversion command will trigger eFSU.

     

    Examples

    The following is sample output from the show issu outagecommand:

    Router# show issu outage slot all
     
    Slot # Card Type                                   MDR Mode          Max Outage Time
    ------ -------------------------------------       -----------       ---------------
         1 CEF720 24 port 1000mb SFP                   WARM_RELOAD        300 secs
         2 1-subslot SPA Interface Processor-600       WARM_RELOAD        300 secs
         3 4-subslot SPA Interface Processor-400       WARM_RELOAD        300 secs

    4 2+4 port GE-WAN RELOAD 360 secs

    The column “Max Outage Time” shows the longest downtime that should be expected for each of the four listed line card types:


    Note


    When there is no eFSU to be performed, and only ISSU will result from the use of the issu runversioncommand, the MDR Mode column in this display shows “NSF_RELOAD” for each line card, to indicate that the line card will not be restarted during the upgrade and therefore will not experience any downtime.


    If you happen to enter the show issu outagecommand outside of the ISSU command sequence, the MDR Mode column in this display shows “INVALID”.

    Verifying the ISSU Process for an MPLS Client

    Perform this task to verify that a particular MPLS client can be upgraded successfully during a particular ISSU session. The commands in this task also can be used to display other details about the ISSU MPLS clients, and should be entered in the order described.

    SUMMARY STEPS

      1.    enable

      2.    show issu clients

      3.    show issu sessions clientID

      4.    show issu negotiated version sessionID

      5.    show issu negotiated capability sessionID

      6.    show issu message types clientID


    DETAILED STEPS
        Command or Action Purpose
      Step 1 enable


      Example:
      Router> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.
       
      Step 2 show issu clients


      Example:
      Router# show issu clients
       

      Lists network applications and protocols currently supported by ISSU.

      You can use this command to discover the client ID that you will need to enter in Steps 3 and 6.

       
      Step 3 show issu sessions clientID


      Example:
      Router# show issu sessions 2002
       

      Tells whether a particular client is compatible with the intended upgrade.

      You can use this command to discover the session ID that you will need to enter in Steps 4 and 5.

       
      Step 4 show issu negotiated version sessionID


      Example:
      Router# 
      show issu negotiated version 33
      
       

      Displays details of the session’s negotiated message version.

       
      Step 5 show issu negotiated capability sessionID


      Example:
      Router# 
      show issu negotiated capability 33
      
       

      Displays results of a negotiation about the client application’s capabilities.

       
      Step 6 show issu message types clientID


      Example:
      Router# show issu message types 2002
       

      Displays the message formats (“types”) and versions supported by the specified client.

       

      Configuration Examples for ISSU MPLS Clients

      To examine any ISSU client, you must specify its unique client ID when entering the show issu sessions command. If you do not already know that client ID, enter the show issu clientscommand in user EXEC or privileged EXEC mode. Each ISSU client on the network will then be listed, with its client ID and client name on the same line, as shown in the following example:

      Router# show issu clients
      Client_ID = 2,  Client_Name = ISSU Proto client,  Entity_Count = 1 
      Client_ID = 3,  Client_Name = ISSU RF,  Entity_Count = 1
      Client_ID = 4,  Client_Name = ISSU CF client,  Entity_Count = 1
      Client_ID = 5,  Client_Name = ISSU Network RF client,  Entity_Count = 1
      Client_ID = 7,  Client_Name = ISSU CONFIG SYNC,  Entity_Count = 1
      Client_ID = 8,  Client_Name = ISSU ifIndex sync,  Entity_Count = 1
      Client_ID = 9,  Client_Name = ISSU IPC client,  Entity_Count = 1
      Client_ID = 10,  Client_Name = ISSU IPC Server client,  Entity_Count = 1 
      Client_ID = 11,  Client_Name = ISSU Red Mode Client,  Entity_Count = 1
      Client_ID = 12,  Client_Name = ISSU EHSA services client,  Entity_Count = 1
      Client_ID = 100,  Client_Name = ISSU rfs client,  Entity_Count = 1
      Client_ID = 110,  Client_Name = ISSU ifs client,  Entity_Count = 1
      Client_ID = 1001,  Client_Name = OC3POS-6,  Entity_Count = 4
      Client_ID = 1002,  Client_Name = C10K ATM,  Entity_Count = 1
      Client_ID = 1003,  Client_Name = C10K CHSTM1,  Entity_Count = 1
      Client_ID = 1004,  Client_Name = C10K CT3,  Entity_Count = 1
      Client_ID = 1005,  Client_Name = C10K GE,  Entity_Count = 1
      Client_ID = 1006,  Client_Name = C10K ET,  Entity_Count = 1
      Client_ID = 1007,  Client_Name = C10K CHE1T1,  Entity_Count = 1
      Client_ID = 1009,  Client_Name = C10K MFE,  Entity_Count = 1
      Client_ID = 1010,  Client_Name = C10K APS,  Entity_Count = 1
      Client_ID = 1013,  Client_Name = C10K CARD OIR,  Entity_Count = 1
      Client_ID = 2002,  Client_Name = CEF Push ISSU client,  Entity_Count = 1
      Client_ID = 2003,  Client_Name = ISSU XDR client,  Entity_Count = 1 
      Client_ID = 2004,  Client_Name = ISSU SNMP client,  Entity_Count = 1
      Client_ID = 2005,  Client_Name = ISSU HDLC Client,  Entity_Count = 1
      Client_ID = 2006,  Client_Name = ISSU QoS client,  Entity_Count = 1
      Client_ID = 2007,  Client_Name = ISSU LSD Label Mgr HA Client,  Entity_Count = 1
      Client_ID = 2008,  Client_Name = ISSU Tableid Client,  Entity_Count = 1
      Client_ID = 2009,  Client_Name = ISSU MPLS VPN Client,  Entity_Count = 1
      Client_ID = 2010,  Client_Name = ARP HA,  Entity_Count = 1
      Client_ID = 2011,  Client_Name = ISSU LDP Client,  Entity_Count = 1
      Client_ID = 2012,  Client_Name = ISSU HSRP Client,  Entity_Count = 1
      Client_ID = 2013,  Client_Name = ISSU ATM Client,  Entity_Count = 1
      Client_ID = 2014,  Client_Name = ISSU FR Client,  Entity_Count = 1
      Client_ID = 2015,  Client_Name = ISSU REDSSOC client,  Entity_Count = 1
      Client_ID = 2019,  Client_Name = ISSU TCP client,  Entity_Count = 1 
      Client_ID = 2020,  Client_Name = ISSU BGP client,  Entity_Count = 1
      Client_ID = 2021,  Client_Name = XDR Int Priority ISSU client,  Entity_Count = 1
      Client_ID = 2022,  Client_Name = XDR Proc Priority ISSU client,  Entity_Count = 1
      Client_ID = 2023,  Client_Name = FIB HWIDB ISSU client,  Entity_Count = 1
      Client_ID = 2024,  Client_Name = FIB IDB ISSU client,  Entity_Count = 1
      Client_ID = 2025,  Client_Name = FIB HW subblock ISSU client,  Entity_Count = 1
      Client_ID = 2026,  Client_Name = FIB SW subblock ISSU client,  Entity_Count = 1
      Client_ID = 2027,  Client_Name = Adjacency ISSU client,  Entity_Count = 1
      Client_ID = 2028,  Client_Name = FIB IPV4 ISSU client,  Entity_Count = 1
      Client_ID = 2030,  Client_Name = MFI Pull ISSU client,  Entity_Count = 1
      Client_ID = 2031,  Client_Name = MFI Push ISSU client,  Entity_Count = 1
      Client_ID = 2051,  Client_Name = ISSU CCM Client,  Entity_Count = 1
      Client_ID = 2052,  Client_Name = ISSU PPP SIP CCM Client,  Entity_Count = 1
      Client_ID = 2053,  Client_Name = ISSU MPLS TE Client,  Entity_Count = 1
      Client_ID = 2054,  Client_Name = ISSU process client,  Entity_Count = 1
      Client_ID = 2089,  Client_Name = MPLS LSPV Push client,  Entity_Count = 1
      .
      .
      .
      .
      Base Clients: 
       Client_Name = ISSU Proto client
       Client_Name = ISSU RF
       Client_Name = ISSU CF client
       Client_Name = ISSU Network RF client
       Client_Name = ISSU CONFIG SYNC
       Client_Name = ISSU ifIndex sync
       Client_Name = ISSU IPC client
       Client_Name = ISSU IPC Server client
       Client_Name = ISSU Red Mode Client
       Client_Name = ISSU EHSA services client
       Client_Name = ISSU rfs client
      Client_Name = ISSU ifs client
       Client_Name = ISSU EM client
       Client_Name = ISSU Platform Medialayer Client
       Client_Name = ISSU FM Client
       Client_Name = ISSU TCAM Manager Client
       Client_Name = ISSU L2 Cmn Client
       Client_Name = ISSU L3 Manager HA Client
       Client_Name = ISSU L3 Manager Client
       Client_Name = ISSU CFIB BASE Client
       Client_Name = ISSU PF CONFIG SYNC Client
       Client_Name = ISSU MLS CEF Client
       Client_Name = ISSU Cat6k Logger Client

      Verifying the ISSU Process for an MPLS LDP Client Example

      This example shows how to verify the ISSU process for an LDP client.

      The first command shows you whether the LDP client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2011
      ---------------------------------------------------------------------
       Client_ID = 2011,  Entity_ID = 1 :
       *** Session_ID = 46,  Session_Name = LDP Session :
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
           4       34   PRIMARY   COMPATIBLE    1        1         0
                                 (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 46
               Nego_Session_Name = LDP Session
               Transport_Mtu = 3948
      

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 46
       Session_ID = 46 :
           Message_Type = 1,  Negotiated_Version = 2,  Message_MTU = 20
           Message_Type = 2,  Negotiated_Version = 2,  Message_MTU = 20
           Message_Type = 3,  Negotiated_Version = 2,  Message_MTU = 4
      

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 46
       Session_ID = 46 :
           Negotiated_Cap_Entry = 1
      

      Finally, to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2011
      ---------------------------------------------------------------------
       Client_ID = 2011,  Entity_ID = 1 :
          Message_Type = 1,  Version_Range = 2 ~ 2
                Message_Ver = 2,    Message_Mtu = 20
          Message_Type = 2,  Version_Range = 2 ~ 2
                Message_Ver = 2,    Message_Mtu = 20
          Message_Type = 3,  Version_Range = 2 ~ 2
                Message_Ver = 2,    Message_Mtu = 4 

      Verifying the ISSU Process for an MPLS VPN Client Example

      This example shows how to verify the ISSU process for an MPLS VPN client.

      The first command shows you whether the VPN client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2009
      ---------------------------------------------------------------------
      Client_ID = 2009,  Entity_ID = 1 :
      *** Session_ID = 39,  Session_Name = MPLS VPN ISSU Session :
         Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
       UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
          3       33   PASSIVE   COMPATIBLE    1        1         0
                                (no policy)
         Negotiation Session Info for This Message Session:
              Nego_Session_ID = 39
              Nego_Session_Name = MPLS VPN ISSU Session
              Transport_Mtu = 3980

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 39
      Session_ID = 39 :
          Message_Type = 1,  Negotiated_Version = 1,  Message_MTU = 32

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 39
      Session_ID = 39 :
      Negotiated_Cap_Entry = 1
      

      Finally,= to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2009
      ---------------------------------------------------------------------
      Client_ID = 2009,  Entity_ID = 1 :
         Message_Type = 1,  Version_Range = 1 ~ 1
               Message_Ver = 1,    Message_Mtu = 32
      

      Verifying the ISSU Process for an MPLS VRF (“Table ID”) Client Example

      This example shows how to verify the ISSU process for an MPLS VRF (“Table ID”) client.

      The first command shows you whether the VRF client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2008
      ---------------------------------------------------------------------
       Client_ID = 2008,  Entity_ID = 1 :
       *** Session_ID = 19,  Session_Name = TABLEID ISSU CF :
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
           4       13   PRIMARY   COMPATIBLE    1        1         0
                                 (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 19
               Nego_Session_Name = TABLEID ISSU CF
               Transport_Mtu = 3948
      
      Router# show issu sessions 2008
      ---------------------------------------------------------------------
       Client_ID = 2008,  Entity_ID = 1 :
       *** Session_ID = 19,  Session_Name = TABLEID ISSU CF :
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
           4       13   PRIMARY   COMPATIBLE    1        1         0
                                 (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 19
               Nego_Session_Name = TABLEID ISSU CF
               Transport_Mtu = 3948
      

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 19
       Session_ID = 19 :
           Message_Type = 1,  Negotiated_Version = 1,  Message_MTU = 44
           Message_Type = 2,  Negotiated_Version = 1,  Message_MTU = 4
      

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 19
      Session_ID = 19 :
      Negotiated_Cap_Entry = 1
      

      Finally, to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2008
      ---------------------------------------------------------------------
       Client_ID = 2008,  Entity_ID = 1 :
          Message_Type = 1,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 44
          Message_Type = 2,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 4
      

      Verifying the ISSU Process for an MPLS LSD Label Manager HA Client Example

      This example shows how to verify the ISSU process for an MPLS LSD Label Manager HA client.

      The first command shows you whether the LSD client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2007
      ---------------------------------------------------------------------
       Client_ID = 2007,  Entity_ID = 1 :
       *** Session_ID = 40,  Session_Name = lsd_ha :
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
           4       30   PRIMARY   COMPATIBLE    1        1         0
                                    (policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 40
               Nego_Session_Name = lsd_ha
               Transport_Mtu = 3948
               Compat_Result: raw_result = COMPATIBLE,  policy_result = COMPATIBLE

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 40
      Session_ID = 40 :
           Message_Type = 1,  Negotiated_Version = 2,  Message_MTU = 8

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 40
      ---------------------------------------------------
        Client_ID = 2007,  Entity_ID = 1,  Session_ID = 40 :
            Negotiated_Cap_Entry = 1

      Finally, to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2007
      ---------------------------------------------------------------------
       Client_ID = 2007,  Entity_ID = 1 :
          Message_Type = 1,  Version_Range = 1 ~ 2
                Message_Ver = 1,    Message_Mtu = 12
                Message_Ver = 2,    Message_Mtu = 8

      Verifying the ISSU Process for an MPLS MFI Pull Client Example

      This example shows how to verify the ISSU process for an MPLS MFI Pull client.

      The first command shows you whether the MFI Pull client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2030
      ---------------------------------------------------------------------
      Client_ID = 2030,  Entity_ID = 1 :
      *** Session_ID = 131073,  Session_Name = MFI Pull 														(6):
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
      	7 		35 	PRIMARY   COMPATIBLE 	1        1         0
                                    (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 131073
               Nego_Session_Name = MFI Pull														(6)
               Transport_Mtu = 4056
      

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 131073
      	Session_ID = 131073:
           Message_Type = 1006,  Negotiated_Version = 1,  Message_MTU = 4
      	Message_Type = 3003,  Negotiated_Version = 1,  Message_MTU = 12
      

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 131073
      	Session_ID = 131073 :
            Negotiated_Cap_Entry = 1
      

      Finally to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2030
      ---------------------------------------------------------------------
      	Client_ID = 2030,  Entity_ID = 1 :
      	Message_Type = 1006,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 4
      	Message_Type = 2004,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 12
      

      Verifying the ISSU Process for an MPLS MFI Push Client Example

      This example shows how to verify the ISSU process for an MPLS MFI Push client.

      The first command shows you whether the MFI Push client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2031
      ---------------------------------------------------------------------
      Client_ID = 2031,  Entity_ID = 1 :
      *** Session_ID = 196646,  Session_Name = MFI Push 														(6):
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
      	7 		36 		PRIMARY   COMPATIBLE 						1        1         0
                                    (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 196646
               Nego_Session_Name = MFI Push														(6)
               Transport_Mtu = 4056
      

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 196646
      Session_ID = 196646:
           Message_Type = 101,  Negotiated_Version = 1,  Message_MTU = 17
      	Message_Type = 105,  Negotiated_Version = 1,  Message_MTU = 31
      

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 196646
      Session_ID = 196646 :
            Negotiated_Cap_Entry = 1
      

      Finally to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2031
      ---------------------------------------------------------------------
      	Client_ID = 2031,  Entity_ID = 1 :
      	Message_Type = 5002,  Version_Range = 1 ~ 2
                Message_Ver = 1,    Message_Mtu = 10
      	Message_Type = 5018,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 39

      Verifying the ISSU Process for an MPLS LSPV Push Client Example

      This example shows how to verify the ISSU process for an MPLS LSVP Push client.

      The first command shows you whether the LSPV Push client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2089
      ---------------------------------------------------------------------
       Client_ID = 2089,  Entity_ID = 1 :
       *** Session_ID = 45,  Session_Name = MPLS LSPV Push (6 ):
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
      	 7		 36	 	PRIMARY   COMPATIBLE    1        1         0
                                 (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 45
               Nego_Session_Name = MPLS LSPV Push ( 6)
               Transport_Mtu = 1438
      

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 45
       Session_ID = 45:
      	Message_Type = 0,  Negotiated_Version = 1,  Message_MTU = 74
      	Message_Type = 1,  Negotiated_Version = 1,  Message_MTU = 120
      	Message_Type = 2,  Negotiated_Version = 1,  Message_MTU = 120
      	Message_Type = 3,  Negotiated_Version = 1,  Message_MTU = 5122
      	Message_Type = 4,  Negotiated_Version = 1,  Message_MTU = 6
      

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 45
      Session_ID = 45:
      Cap_Type = 0				Cap_Result = 1					No cap value assigned 
      

      Finally to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2089
      ---------------------------------------------------------------------
       Client_ID = 2089,  Entity_ID = 1 :
          Message_Type = 0,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 74
          Message_Type = 1,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 120
      	Message_Type = 2,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 120
          Message_Type = 3,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 5122
      	Message_Type = 4,  Version_Range = 1 ~ 1
                Message_Ver = 1,    Message_Mtu = 6
      

      Verifying the ISSU Process for an MPLS TE Client Example

      This example shows how to verify the ISSU process for an MPLS TE client.

      The first command shows you whether the TE client’s old and new software versions are compatible, and therefore are able to make use of the ISSU opportunity:

      Router# show issu sessions 2053
      ---------------------------------------------------------------------
       Client_ID = 2053,  Entity_ID = 1 :
       *** Session_ID = 84,  Session_Name = RSVP HA Session :
          Peer   Peer  Negotiate  Negotiated   Cap      Msg     Session
        UniqueID  Sid    Role       Result   GroupID  GroupID  Signature
          22       94   PRIMARY   COMPATIBLE    1        1         0
                                 (no policy)
          Negotiation Session Info for This Message Session:
               Nego_Session_ID = 84
               Nego_Session_Name = RSVP HA Session
               Transport_Mtu = 1392

      Now you can take the session ID displayed in the previous command’s output and enter it into the next command, in order to see the negotiated message version:

      Router# show issu negotiated version 84
      Session_ID = 84 :
           Message_Type = 1,  Negotiated_Version = 2,  Message_MTU = 1024

      Next you can enter the same session ID into the following command to display the capability negotiation result:

      Router# show issu negotiated capability 84
      Session_ID = 84 :
           Cap_Type = 0,     Cap_Result = 1     No cap value assigned

      Finally to see which message types and versions are supported by this particular client, you enter the client ID into the following command:

      Router# show issu message types 2053
      ---------------------------------------------------------------------
       Client_ID = 2053,  Entity_ID = 1 :
          Message_Type = 1,  Version_Range = 1 ~ 2
                Message_Ver = 1,    Message_Mtu = 1024
                Message_Ver = 2,    Message_Mtu = 1024

      Additional References

      The following sections provide references related to the NSF/SSO--MPLS LDP and LDP Graceful Restart feature.

      Related Documents

      Related Topic

      Document Title

      Stateful switchover

      Stateful Switchover

      MPLS Label Distribution Protocol

      MPLS Label Distribution Protocol (LDP)

      MPLS LDP commands

      Cisco IOS Multiprotocol Label Switching Command Reference

      Cisco nonstop forwarding

      Cisco Nonstop Forwarding

      High availability commands

      Cisco IOS High Availability Command Reference

      Standards

      Standard

      Title

      No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.

      --

      MIBs

      MIB

      MIBs Link

      MPLS Label Distribution Protocol MIB Version 8 Upgrade

      To locate and download MIBs for selected platforms, Cisco IOS XE software releases, and feature sets, use Cisco MIB Locator found at the following URL:

      http:/​/​www.cisco.com/​go/​mibs

      RFCs

      RFC

      Title

      RFC 3036

      LDP Specification

      RFC 3478

      Graceful Restart Mechanism for Label Distributio n

      Technical Assistance

      Description

      Link

      The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

      To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

      Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

      http:/​/​www.cisco.com/​techsupport

      Feature Information for ISSU MPLS Clients

      The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

      Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

      Table 2 Feature Information for ISSU MPLS Clients

      Feature Name

      Releases

      Feature Information

      ISSU MPLS Clients

      12.2(28)SB 12.2(33) SRB-1

      MPLS applications can be upgrading using the In Service Software Upgrade (ISSU) process and the enhanced Fast Software Upgrade (eFSU) process. Thus, MPLS applications are considered ISSU’s MPLS clients. The ISSU process allows Cisco IOS software at the router level to be updated or otherwise modified while packet forwarding continues. At the line-card level , the eFSU process minimizes line-card downtime during such upgrades to between 30 and 90 seconds, by loading the new line-card image before the ISSU switchover occurs from the active to the standby Route Processor (RP).

      In 12.2(28)SB, the ISSU feature was introduced.

      In 12.2(33)SRB-1, the LSPV Push and TE clients and the eFSU functionality were added.

      The following commands were introduced or modified: show issu clients, show issu entities, show issu message types, show issu negotiated, show issu outage, show issu sessions.

      Glossary

      DSCP --differentiated services code point. Six bits in the IP header, as defined by the Internet Engineering Task Force (IETF). These bits determine the class of service provided to the IP packet.

      Fast Reroute --A mechanism for protecting Multiprotocol Label Switching (MPLS) traffic engineering (TE) label switched paths (LSPs) from link and node failure by locally repairing the LSPs at the point of failure, allowing data to continue to flow on them while their headend routers attempt to establish end-to-end LSPs to replace them. Fast reroute (FRR) locally repairs the protected LSPs by rerouting them over backup tunnels that bypass failed links or nodes.

      graceful restart --A process for helping a Route Processor (RP) restart after a node failure has occurred.

      headend --The router that originates and maintains a given label switched path (LSP). This is the first router in the LSP’s path.

      hello instance --A mechanism that implements the Resource Reservation Protocol (RSVP) hello extensions for a given router interface address and remote IP address. Active hello instances periodically send hello request messages, expecting Hello ACK messages in response. If the expected ACK message is not received, the active hello instance declares that the neighbor (remote IP address) is unreachable (that is, it is lost). This can cause LSPs crossing this neighbor to be fast rerouted.

      IGP --Interior Gateway Protocol. Internet protocol used to exchange routing information within an autonomous system. Examples of common Internet IGPs include Interior Gateway Routing Protocol (IGRP), Open Shortest Path First (OSPF), and Routing Information Protocol (RIP).

      ISSU --In Service Software Upgrade. Software upgrade without service interruption.

      label --A short, fixed-length data identifier that tells switching nodes how to forward data (packets or cells).

      LSP --label switched path. A configured connection between two routers, in which Multiprotocol Label Switching (MPLS) is used to carry packets.

      MPLS --Multiprotocol Label Switching. A method for forwarding packets (frames) through a network. MPLS enables routers at the edge of a network to apply labels to packets (frames). ATM switches or existing routers in the network core can switch packets according to the labels.

      RSVP --Resource Reservation Protocol. A protocol that supports the reservation of resources across an IP network. Applications running on IP end systems can use RSVP to indicate to other nodes the nature (bandwidth, jitter, maximum burst, and so on) of the packet streams they want to receive.

      state --Information that a router must maintain about each label switched path (LSP). The information is used for rerouting tunnels.

      tailend --The router upon which a label switched path (LSP) is terminated. This is the last router in the LSP’s path.

      TE --traffic engineering. The techniques and processes used to cause routed traffic to travel through the network on a path other than the one that would have been chosen if standard routing methods had been used.