Supported and unsupported features of the GCC interface

This table lists supported and unsupported features for remote node management using the GCC interface.
Table 1. Feature Support Overview:

Feature/Functionality

Supported on GCC Interface?

Notes

gRPC protocol

No

gRPC is not supported over the GCC interface.

Open Config

No

Not supported due to lack of gRPC support.

Streaming telemetry

No

Not supported due to lack of gRPC support.

Tx and Rx packet count statistics

Yes

Only Tx and Rx packet count information is available in GCC

Remote node management (after initial provisioning)

Yes

Devices can be managed over GCC only when connected through the management network using GCC.

Initial provisioning and bring-up via GCC

No

Must use console or management Ethernet interface for initial setup.

Remote management after headless/HA event

May be impacted

Events like reloads or driver restarts at intermediate nodes may affect management of subsequent nodes.
IP fragmentation for SCP protocol

No

Not supported; reduce packet size to less than 1454 bytes as a workaround.

TCP MSS configuration to avoid fragmentation

Yes

Use tcp mss <maximum segment size> in global config mode.

Coherent DSP controller (QXP card) GCC0 interface

Yes

Supported on QXP card.

GCC0 speed on QXP card

Yes

7.7 Mbps.

Note

For operations not supported on the GCC interface, use the console or management Ethernet interface as alternatives. For SCP protocol, configure TCP MSS or IPv4 MTU settings to avoid IP fragmentation issues.

Supported protocols

These protocols are supported over the GCC interface:

  • PING

  • SSH

  • TELNET

  • SCP

  • TFTP

  • FTP

  • SFTP

  • HTTP

  • HTTPS

  • OSPF

Enable the GCC interface

Use this task to enable GCC0, GCC1, or GCC2 interfaces on various line cards (1.2T, OTN-XP) to support management and communication channels.

Procedure

Step 1

Enter configuration mode.

Step 2

Configure the controller and the GCC interface for a line card.

If you want to configure

Then use the command

GCC2 interface on the 1.2T card

controller odu4 R/S/I/P/L gcc2

GCC0 interface on the 1.2T card

 controller CoherentDSP R/S/I/P/L gcc2

GCC0 interface for the OTN-XP card

 controller {otu2 | otu2e | otu4} R/S/I/P/L gcc0

GCC1 interface for the OTN-XP card

 controller {odu2 | odu2e | odu4 | oducn} R/S/I/P/L gcc1

Example:

This sample configuration enables the GCC2 interface for the 1.2T line card.

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller odu4 0/1/0/0/1
RP/0/RP0/CPU0:ios(config-otu)#gcc2
RP/0/RP0/CPU0:ios(config-otu)#commit
RP/0/RP0/CPU0:ios(config-otu)#exit

This sample configuration enables the GCC0 interface for the 1.2T line card.

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller CoherentDSP0/0/1/1
RP/0/RP0/CPU0:ios(config-otu)#gcc0
RP/0/RP0/CPU0:ios(config-otu)#commit
RP/0/RP0/CPU0:ios(config-otu)#exit

This sample configuration enables the GCC0 interface for the OTN-XP line card.

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller otu2 0/0/0/4/1
RP/0/RP0/CPU0:ios(config-otu)#gcc0
RP/0/RP0/CPU0:ios(config-otu)#commit
RP/0/RP0/CPU0:ios(config-otu)#exit

This sample configuration enables the GCC1 interface for the OTN-XP line card.

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller odu2 0/0/0/4/1
RP/0/RP0/CPU0:ios(config-otu)#gcc1
RP/0/RP0/CPU0:ios(config-otu)#commit
RP/0/RP0/CPU0:ios(config-otu)#exit

Configure the GCC interface

Use this task to configure the GCC0, GCC1, and GCC2 interfaces on 1.2T and OTN-XP cards using static or loopback IP addresses.

Procedure

Step 1

Enter configuration mode.

Step 2

Specify the GCC2 interface for a line card.

If you want to configure

Then use the command

GCC2 interface on the 1.2T card

interface gcc2 R/S/I/P/L

GCC0 interface on the 1.2T card

 interface gcc0 R/S/I/P

GCC0 interface on the OTN-XP card

 interface gcc0 R/S/I/P

GCC1 interface on the OTN-XP card

 interface gcc1 R/S/I/P

Step 3

Use the command ipv4 address ipv4-address net-mask to set the IPv4 address for the interface.

Example:

This sample configures the GCC2 interface using the static IP address on the 1.2T line card

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#interface gcc2 0/1/0/0/1
RP/0/RP0/CPU0:ios(config-if)#ipv4 address 198.51.100.244 255.255.255.0
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit
RP/0/RP0/CPU0:ios#show run interface gcc2 0/1/0/0/1
interface GCC20/1/0/0/1
ipv4 address 10.1.1.1 255.255.255.0
!

This sample configures the GCC2 interface using the loopback IP address on 1.2T card.

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:R2(config)#interface gcc2 0/1/0/0/1
RP/0/RP0/CPU0:R2(config-if)#ipv4 unnumbered loopback 0
RP/0/RP0/CPU0:ios(config-if)#exit

This sample checks the status of GCC2 interface.

RP/0/RP0/CPU0:ios#show ipv4 interface brief
Wed Sep 22 17:10:04.190 IST
Interface IP-Address Status Protocol Vrf-Name
GCC20/0/0/0/1 198.51.100.234 Up Up default
GCC20/3/0/1/3 198.51.100.244 Up Up default
Loopback0 198.51.100.224 Up

This sample configures the GCC0 interface using the static IP address on 1.2T or OTN-XP card.enables the GCC1 interface for the OTN-XP line card. 

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#interface gcc0 0/1/0/0
P/0/RP0/CPU0:ios(config-if)#ipv4 address 198.51.100.244 255.255.255.0
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit
RP/0/RP0/CPU0:ios#show run interface gcc0 0/1/0/0
interface GCC00/1/0/0
ipv4 address 198.51.100.244 255.255.255.0
!

This sample configures the the GCC0 interface using the loopback IP address on 1.2T or OTN-XP card.

RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:R2(config)#interface gcc0 0/1/0/0
RP/0/RP0/CPU0:R2(config-if)#ipv4 unnumbered loopback 0
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit

Configure static routes over the GCC interface

Use this task to configure the router to forward packets for specific networks or hosts via the GCC interface using manually defined routes.

Procedure

Step 1

Enter configuration mode.

Step 2

Enter the router static configuration mode.

Step 3

Use the command address-family ipv4 unicast ip4 address default-gateway to enter address family configuration mode. This step also configures a routing session using standard IPv4 address prefixes.

Example:


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#router static address-family ipv4 unicast 0.0.0.0/0 10.105.57.1
RP/0/RP0/CPU0:ios(config)#exit

Configure OSPF routes over the GCC interface

Enable OSPF dynamic routing between gateway and remote nodes using GCC interfaces.

This task enables OSPF over GCC interfaces, which facilitates efficient OSPF communication in specialized network environments.

Procedure

  Command or Action Purpose

Step 1

Enter configuration mode and enable the OSPF routing process using the command router ospf process-id router-id ip-address

Example:

Step 2

Assign the OSPF area and specify the interfaces to include using the command area area-id interface type R/S/I/P/L

Step 3

On the remote node, redistribute connected routes into OSPF, using the command redistribute connected.

Step 4

Exit the configuration mode upon completion.

Example:

Gateway Node:


configure
router ospf 1
router-id 192.0.2.89 area 0                                                                                                        
  interface Loopback0                                                                                          
  !                                                                                                            
  interface MgmtEth0/RP0/CPU0/1                                                                                
  !                                                                                                            
  interface GCC20/0/0/0/1                                                                                      
  !                                                                                                            
  interface GCC20/0/0/0/2

Remote Node:


configure
router ospf 1  
router-id 192.0.2.92
redistribute connected                                                                                             
 area 0                                                                                                        
  interface Loopback0                                                                                          
  !                                                                                                            
  interface GCC20/0/0/0/1                                                                                      
  !                                                                                                            
  interface GCC20/0/0/0/2

OSPF is configured over GCC interfaces, enabling gateway and remote nodes to dynamically exchange routing information.

iBGP supports over GCC interfaces

iBGP support over GCC interfaces is a routing capability that

  • allows external devices to exchange BGP routes through the management interfaces of NCS 1004 systems,

  • enables NCS 1004 devices to advertise local networks and manage them using BGP-learned paths, and

  • establishes iBGP sessions over GCC for exchanging BGP routes.

You can configure VRF on the GCC management interfaces (port 0 and port 1) of the NCS 1004 device to achieve traffic isolation between the two management ports.

NCS 1004 supports GCC0 and GCC2 interfaces for the 1.2T line card, allowing greater flexibility and connectivity options. The device advertises its local networks using BGP and manages them through paths learned from the iBGP sessions established over the GCC interfaces.

Restrictions for iBGP Support Using GCC

  • IP fragmentation is not supported on the GCC interface.

  • The BGP configuration over Open Config (OC) is not supported.


Note

The limitations of Remote Node Management Using GCC are applicable for iBGP Support Using GCC. For more information, see Limitations of Remote Node Management.

Caution: Follow restrictions for iBGP support using GCC

Consider these restrictions when implementing iBGP support using GCC:

  • Do not use IP fragmentation on the GCC interface; this function is not supported.

  • Do not configure BGP over Open Config (OC) on GCC interfaces; this configuration is not supported.

  • Observe all limitations found for Remote Node Management using GCC; these also apply to iBGP support using GCC

Enabling the GCC Interface

To enable the GCC2 interface, use the following commands:

configure
controller odu4 R/S/I/P/L
gcc2
commit
exit

To enable the GCC0 interface, use the following commands:

configure
controller CoherentDSP R/S/I/P
gcc0
commit
exit

Configuring the Management Interface

To configure the management Ethernet interface with VRF, use the following commands:


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios#interface MgmtEth0/RP0/CPU0/1
RP/0/RP0/CPU0:ios(config-if)#vrf transport-vrf
RP/0/RP0/CPU0:ios(config-if)#ipv4 address ipv4-address
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit

The following example displays how to configure the management Ethernet interface with VRF. 


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios#interface MgmtEth0/RP0/CPU0/1
RP/0/RP0/CPU0:ios(config-if)#vrf transport-vrf
RP/0/RP0/CPU0:ios(config-if)#ipv4 address 192.0.2.1 255.255.255.255
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit

Configuring the Loopback Interface

To configure the loopback interface 0 with VRF, use the following commands: 


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios#interface Loopback0
RP/0/RP0/CPU0:ios(config-if)#vrf transport-vrf
RP/0/RP0/CPU0:ios(config-if)#ipv4 address ipv4-address
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit

The following example displays how to configure the loopback interface 0 with VRF. 


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios#interface Loopback0
RP/0/RP0/CPU0:ios(config-if)#vrf transport-vrf
RP/0/RP0/CPU0:ios(config-if)#ipv4 address 192.0.2.1 255.255.255.255
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit

Configuring the GCC interface

To configure the GCC2 interface with VRF and static IP address, use the following commands:

configure

interface gcc2 R/S/I/P/L

vrf transport-vrf

ipv4 address ipv4-address

commit

exit

To configure the GCC0 interface with VRF and static IP address, use the following commands:

configure

interface gcc0 R/S/I/P

vrf transport-vrf

ipv4 address ipv4-address

commit

exit

Examples

The following sample displays how to configure the GCC2 interface with VRF and static IP address.


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#interface gcc2 0/1/0/0/1
RP/0/RP0/CPU0:ios(config-if)#vrf transport-vrf
P/0/RP0/CPU0:ios(config-if)#ipv4 address 198.51.100.5 255.255.255.0
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit

The following sample displays how to configure the GCC2 interface using loopback IP address.


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:R2(config)#interface gcc2 0/1/0/0/1
RP/0/RP0/CPU0:R2(config-if)#ipv4 unnumbered loopback 0
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit

The following sample displays how to configure the GCC0 interface with VRF and static IP address.


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#interface gcc0 0/1/0/0
RP/0/RP0/CPU0:ios(config-if)#vrf transport-vrf
P/0/RP0/CPU0:ios(config-if)#ipv4 address 198.51.100.2 255.255.255.0
RP/0/RP0/CPU0:ios(config-if)#commit
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit

The following sample displays how to configure the GCC0 interface using the loopback IP address.


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:R2(config)#interface gcc0 0/1/0/0
RP/0/RP0/CPU0:R2(config-if)#ipv4 unnumbered loopback 0
RP/0/RP0/CPU0:ios(config-if)#exit
RP/0/RP0/CPU0:ios(config)#exit

Verifying iBGP Support Using GCC

To verify BGP support using GCC configuration, use the following show commands: 


RP/0/RP0/CPU0:ios#show bgp vrf transport-vrf neighbors brief
Neighbor        Spk    AS Description                          Up/Down  NBRState
198.51.100.0     0     200                                    00:51:49 Established
198.51.100.1       0    100                                    00:50:32 Established


RP/0/RP0/CPU0:ios#show bgp vrf transport-vrf                                        
BGP VRF transport-vrf, state: Active                                               
BGP Route Distinguisher: 192.0.2.7:0                                                 
VRF ID: 0x60000002                                                                 
BGP router identifier 192.0.2.7, local AS number 100                                 
Non-stop routing is enabled                                                        
BGP table state: Active                                                            
Table ID: 0xe0000002   RD version: 51                                              
BGP main routing table version 51                                                  
BGP NSR Initial initsync version 11 (Reached)                                      
BGP NSR/ISSU Sync-Group versions 0/0                                               
 
Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete                      
   Network            Next Hop            Metric LocPrf Weight Path 
Route Distinguisher: 192.0.2.7:0 (default for vrf transport-vrf)      

*> 209.165.201.30/27        198.51.100.0              0         0 200 i
*> 209.165.201.28/27        0.0.0.0                   0         32768 i    
*> 209.165.201.26/27        0    100      0 i      
*> 209.165.201.24/27       198.51.100.2               0    100      0 300 i



RP/0/RP0/CPU0:ios#show bgp vrf transport-vrf                                        
BGP VRF transport-vrf, state: Active                                               
BGP Route Distinguisher: 203.0.113.10:0                                                 
VRF ID: 0x60000002                                                                 
BGP router identifier 203.0.113.10, local AS number 100                                 
Non-stop routing is enabled                                                        
BGP table state: Active                                                            
Table ID: 0xe0000002   RD version: 51                                              
BGP main routing table version 51                                                  
BGP NSR Initial initsync version 11 (Reached)                                      
BGP NSR/ISSU Sync-Group versions 0/0                                               
 
Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete                      
   Network            Next Hop            Metric LocPrf Weight Path 
Route Distinguisher: 203.0.113.10:0 (default for vrf transport-vrf)      

*> 209.165.201.30/27        198.51.100.0              0             0 200 i
*> 209.165.201.28/27        0.0.0.0                   0             32768 i    
*>i209.165.201.26/27        198.51.100.12               0    100      0 i      
*>i209.165.201.24/27       198.51.100.24               0    100      0 300 i

iBGP configuration parameters for GCC interfaces

This table summarizes the configuration required for enabling iBGP sessions between two NCS 1004 devices.

Use case:

Consider two NCS 1004 devices, R2 and R3, directly connected through GCC0 interfaces. In this use case, R2 (with IP address 198.51.100.21) and R3 (with IP address 198.51.100.22) are configured with the commands to establish an iBGP session using their respective transport-VRFs.

R2 is connected through GCC0 0/0/0/0 interface with IP address of 198.51.100.21 and R3 is connected through GCC0 0/1/0/0 with IP address of 198.51.100.22. The R2 and R3 devices are connected to external devices through management interfaces.

Table 2. iBGP configuration commands for NCS 1004

Configuration on R2

Configuration on R3

Global Configuration on R2


hw-module location 0/0
 mxponder
  trunk-rate 600G
  client-rate 100GE

vrf transport-vrf
 address-family ipv4 unicast

Global Configuration on R3


hw-module location 0/0
 mxponder
  trunk-rate 600G
  client-rate 100GE

vrf transport-vrf
 address-family ipv4 unicast

Interface Configuration on R2


interface Loopback0
 vrf transport-vrf
 ipv4 address 192.0.2.2 255.255.255.255

interface MgmtEth0/RP0/CPU0/1
 vrf transport-vrf
 ipv4 address 198.51.100.25 255.255.255.0

controller ODU40/0/0/0/2
 gcc2

interface GCC20/0/0/0/2
 vrf transport-vrf
 ipv4 address 198.51.100.21 255.255.255.0

Interface Configuration on R3


interface Loopback0
 vrf transport-vrf
 ipv4 address 203.0.113.3 255.255.255.255

interface MgmtEth0/RP0/CPU0/1
 vrf transport-vrf
 ipv4 address 198.51.100.32 255.255.255.0

controller ODU40/1/0/0/2
 gcc2

interface GCC20/1/0/0/2
 vrf transport-vrf
 ipv4 address 198.51.100.22 255.255.255.0

Route-policy Configuration on R2


route-policy PASS-ALL
  pass
end-policy

Router Policy Configuration on R3


route-policy PASS-ALL
  pass
end-policy

Static Route Configuration on R2


router static
 address-family ipv4 unicast
  0.0.0.0/0 198.51.100.28
 !
 vrf transport-vrf
  address-family ipv4 unicast
   198.51.100.0/24 198.51.100.22

Static Route Configuration on R3


router static
 address-family ipv4 unicast
  0.0.0.0/0 198.51.100.28

 vrf transport-vrf
  address-family ipv4 unicast
   198.51.100.0/24 198.51.100.21

BGP Configurationon R2


router bgp 100
 bgp router-id 192.0.2.123
 address-family vpnv4 unicast
 !
 vrf transport-vrf
  rd auto
  address-family ipv4 unicast
   network 203.0.113.1/32
  !
  neighbor 198.51.100.22
   remote-as 100
   address-family ipv4 unicast
    route-policy PASS-ALL in
    route-policy PASS-ALL out
    next-hop-self
   !

BGP Configuration on R3


router bgp 100
 bgp router-id 192.0.2.124
 address-family vpnv4 unicast
 !
 vrf transport-vrf
  rd auto
  address-family ipv4 unicast
   network 203.0.113.3/32
  !
  neighbor 198.51.100.21
   remote-as 100
   address-family ipv4 unicast
    route-policy PASS-ALL in
    route-policy PASS-ALL out
    next-hop-self
   !

BGP Verification on R2


RP/0/RP0/CPU0:ios#show bgp sessions
Mon Jul 20 14:47:30.378 UTC

Neighbor        VRF                   Spk    AS   InQ  OutQ  NBRState     NSRState
198.51.100.22   transport-vrf           0   100     0     0  Established  None

BGP Verification on R3


RP/0/RP0/CPU0:regen#show bgp sessions
Tue Jul 21 02:50:14.134 UTC  

Neighbor        VRF                   Spk    AS   InQ  OutQ  NBRState     NSRState
198.51.100.21   transport-vrf           0   100     0     0  Established  None