A DHCP server must be configured for IPv4, IPv6, or both communication protocols.

Note

For DHCPv6, a routing advertisement (RA) message must be sent to all nodes in the network that indicates which method is to be used to obtain the IPv6 address. Configure Router-advertise-daemon (radvd, install using yum install radvd) to allow the client to send the DHCP request. For example: interface eth3 { AdvSendAdvert on; MinRtrAdvInterval 60; MaxRtrAdvInterval 180; AdvManagedFlag on; AdvOtherConfigFlag on; prefix 2001:1851:c622:1::/64 { AdvOnLink on; AdvAutonomous on; AdvRouterAddr off; }; };

To setup a DHCP server:

1. Create the dhcpd.conf file (for IPv4, IPv6 or both communication protocols), dhcpv6.conf file (for IPv6) or both in the /etc/ directory. This configuration file stores the network information such as the path to the script, location of the ISO install file, location of the provisioning configuration file, serial number, MAC address of the chassis.

2. Test the server once the DHCP server is running:

   For example, for ipv4:

   1. Use MAC address of the chassis:

      host ncs1001 
      {
      hardware ethernet ab:cd:ef:01:23:45;
      fixed-address <ip address>;
      filename "http://<httpserver-address>/<path-to-image>/ncs1001-mini-x.iso";
      }

      Ensure that the above configuration is successful.
   2. Use serial number of the chassis:

      host demo {
      option dhcp-client-identifier "<chassis-serial-number>";
        filename "http://<IP-address>/<hardware-platform>-mini-x.iso";
        fixed-address <IP-address>;
      }

      The serial number of the chassis is derived from the BIOS and is used as an identifier.

      Example

      
      host 10.89.205.202 {
             hardware ethernet 40:55:39:56:0c:e8;
                if exists user-class and option user-class = "iPXE" {
                filename "http://10.89.205.127/box1/ncs1001-mini-x-7.1.1.iso";
             } else {
                 filename "http://10.89.205.127/box1/StartupConfig.cfg";
             }
             fixed-address 10.89.205.202;
          }
      

      For example, for ipv6:

      1. Use serial number of the chassis:

         The serial number of the chassis is derived from the XR command 'show inventory' and is used as an identifier. The S/N must be converted in an ipv6 DUID format.

         host ncs1001 {
           host-identifier  option dhcp-client-identifier "<IPV6-DIUD>";
           filename "<http,tftp>://<IPv6-dhcp-server-address>/<hardware-platform>-mini-x.iso";
         }

         Example

         host mys-p1b-212 {
                        
            # PID: NCS1001-K9        , VID: V01, SN: CAT2018B02M
         
            host-identifier option dhcp6.client-id 00:02:00:00:00:09:43:41:54:32:30:31:38:42:30:32:4d:00;
         
            if exists dhcp6.user-class and substring(option dhcp6.user-class, 2, 4) = "iPXE" {
              option dhcp6.bootfile-url "http://[2001:420:4491:2005::227:11]/rosco/mys-p1b-212/ncs1001-mini-mod.iso";
            }
            else {
              option dhcp6.bootfile-url "http://[2001:420:4491:2005::227:11]/rosco/mys-p1b-212/ztp.ipv6.sh";
            }
         }
         

         Here a simple shell script that converts from chassis S/N to DUID

         Example

         #! /bin/sh
         
         # Comply with IPv6 EN-DUID - see DHCPv6 RFC for detail
         ## 00:02 = Indicate Enterprise number based DUID
         ## 00:00:00:09 = CIsco Enterprise number
         ## 00 = Terminator
         
         SERIALNUMBER=$1
         en_duid=0002
         cisco_en=00000009
         
         sn=`xxd -l11 -pu <<< ${SERIALNUMBER}`
         null=00
         DHCPv6_DUID=`sed 's/\(..\)/\1:/g;s/:$//' <<< ${en_duid}${cisco_en}${sn}${null}`
         
         echo $DHCPv6_DUID
         

Before you use the iPXE boot, ensure that:

• DHCP server is set and is running.

• You have logged in to the System Admin console using the admin command.

hw-module location all bootmedia network reload

sysadmin-vm:0_RP0# hw-module location all bootmedia network reload
Wed Dec 23 15:29:57.376 UTC
Reload hardware module ? [no,yes]

 
iPXE 1.0.0+ (3e573) -- Open Source Network Boot Firmware -- http://ipxe.org
Features: DNS HTTP TFTP VLAN EFI ISO9660 NBI Menu
Trying net0...
net0: c4:72:95:a6:14:e1 using dh8900cc on PCI01:00.1 (open)
[Link:up, TX:0 TXE:0 RX:0 RXE:0]
Configuring (net0 c4:72:95:a6:14:e1).................. Ok << Talking to DHCP/PXE server to obtain network information
net0: 10.37.1.101/255.255.0.0 gw 10.37.1.0
net0: fe80::c672:95ff:fea6:14e1/64
net0: 2001:1800:5000:1:c672:95ff:fea6:14e1/64 gw fe80::20c:29ff:fefb:b9fe
net1: fe80::c672:95ff:fea6:14e3/64 (inaccessible)
Next server: 10.37.1.235
Filename: http://10.37.1.235/ncs1001/ncs1001-mini-x.iso
http://10.37.1.235/ncs1001/ncs1001-mini-x.iso ncs1000/ncs1001-mini-x.iso... 58% << Downloading file as indicated by DHCP/PXE server to boot install image

When you boot the device, the ZTP process initiates automatically if the device does not have a prior configuration.

Based on the business need, you can use a configuration or script file to initiate the ZTP process.

The configuration file content starts with !! IOS XR.

The following is the sample configuration file for IPv4. You can automate all the configurations.

!! IOS XR Configuration version = 6.3.2
!
telnet vrf default ipv4 server max-servers 20
!
vty-pool default 0 20 line-template default
!
interface MgmtEth0/RP0/CPU0/0
 ipv4 address dhcp
 no shutdown
!
router static
 address-family ipv4 unicast
  0.0.0.0/0 10.77.132.1
!
end

The following is the sample configuration file for IPv6.

!! IOS XR Configuration version = 7.10.1
!
telnet vrf default ipv6 server max-servers 20
!
vty-pool default 0 20 line-template default
!
interface MgmtEth0/RP0/CPU0/0
 ipv6 address dhcp6
 no shutdown
!
router static
 address-family ipv6 unicast
  2001:db8:1000::/36 2001:db8:2000:2::1
!
end

ZTP logs its operation on the flash file system in the directory /disk0:/ztp/. ZTP logs all the transaction with the DHCP server and all the state transition.

The following example displays the execution of a simple configuration script that is downloaded from a management interface:

2023-05-12 14:43:18,406   5845 [Env          ] INF: MgmtDhcp4Fetcher fetcher created.
2023-05-12 14:43:18,482   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:idle. Processing work: [privileged] start an engine. done = False
2023-05-12 14:43:18,484   5845 [Engine       ] INF: MgmtDhcp4Fetcher, current state:active: state changed to active
2023-05-12 14:43:18,508   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Monitor fetcher work for ZAdmin. done = False
2023-05-12 14:43:18,585   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: epoch work. done = False
2023-05-12 14:43:18,586   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: [privileged] getting engine status. done = False
2023-05-12 14:43:18,587   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: Bringing up interfaces before next retry. done = False
2023-05-12 14:43:18,589   5845 [Port         ] DEB: <Port count=1>: bringing interface(s) up "MgmtEth0/RP0/CPU0/0"
2023-05-12 14:43:18,624   5845 [Port         ] DEB: Saving 1 interfaces to /disk0:/ztp/xr_config/interface_list
2023-05-12 14:43:18,626   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: Filtering up interfaces for MgmtDhcp4Fetcher. done = False
2023-05-12 14:43:18,627   5845 [Management   ] DEB: Determining operstate of interface: brXRmgmt1
2023-05-12 14:43:18,666   5845 [Port         ] DEB: Filtered up interfaces: [Name: MgmtEth0/RP0/CPU0/0 (Type: Management) (Up: False)]
2023-05-12 14:43:18,670   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: Setup interfaces for MgmtDhcp4Fetcher. done = False
2023-05-12 14:43:18,671   5845 [Env          ] INF: Env::getVlanIDs: vlan.mode:2
2023-05-12 14:43:18,672   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: Start Dhclient for MgmtDhcp4Fetcher. done = False
2023-05-12 14:43:18,687   5845 [Port         ] DEB: <Dhclient count=1>: started dhclient using "ip netns exec xrnns /sbin/dhclient -4 -cf /etc/dhcp/dhclient.conf.ztp -lf /var/lib/dhcp/dhclient.leases.ztp -sf /etc/dhcp/dhclient-script.ztp2 brXRmgmt1"
2023-05-12 14:43:19,090   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Checking for username configuration. done = False
2023-05-12 14:43:19,630   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Monitor fetcher work for ZAdmin. done = False
2023-05-12 14:43:19,692   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: [privileged] getting engine status. done = False
2023-05-12 14:43:20,696   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Monitor fetcher work for ZAdmin. done = False
2023-05-12 14:43:20,797   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: [privileged] getting engine status. done = False
2023-05-12 14:43:21,099   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Sending standby sync message. done = False
2023-05-12 14:43:21,212   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: [privileged] getting engine status. done = False
2023-05-12 14:43:21,700   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:active. Processing work: Monitor dhclient for MgmtDhcp4Fetcher on interface ['brXRmgmt1']. done = False
2023-05-12 14:43:21,704   5845 [MgmtDhcp4Fetcher] DEB: Received DHCP4 response
2023-05-12 14:43:21,705   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) reason=BOUND
2023-05-12 14:43:21,706   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) interface=brXRmgmt1
2023-05-12 14:43:21,706   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_ip_address=10.58.227.177
2023-05-12 14:43:21,707   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_network_number=10.58.227.0
2023-05-12 14:43:21,708   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_subnet_mask=255.255.255.0
2023-05-12 14:43:21,708   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_broadcast_address=10.58.227.255
2023-05-12 14:43:21,709   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_routers=10.58.227.1
2023-05-12 14:43:21,710   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_dhcp_server_identifier=10.58.227.11
2023-05-12 14:43:21,711   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_domain_name=cisco.com
2023-05-12 14:43:21,711   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_domain_name_servers=198.51.100.3 198.51.100.1
2023-05-12 14:43:21,712   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_filename=http://10.58.227.11/rosco/mys-p1b-212/ztp.sh
2023-05-12 14:43:21,713   5845 [MgmtDhcp4Fetcher] INF: (dhclient env) new_ip6_prefixlen=64
2023-05-12 14:43:21,714   5845 [Engine       ] INF: MgmtDhcp4Fetcher, current state:active, exit code:success
2023-05-12 14:43:21,815   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Monitor fetcher work for ZAdmin. done = False
2023-05-12 14:43:21,828   5845 [Port         ] DEB: Dhclient processes:
root      7033  0.0  0.0  31096  7312 ?        Ss   14:46   0:00 /sbin/dhclient -4 -cf /etc/dhcp/dhclient.conf.ztp -lf /var/lib/dhcp/dhclient.leases.ztp -sf /etc/dhcp/dhclient-script.ztp2 brXRmgmt1
root      7052  0.0  0.0  20316  1592 ?        S    14:46   0:00 /bin/sh -c ps aux | grep dhclient
root      7054  0.0  0.0  16248   948 ?        Sl   14:46   0:00 grep dhclient
2023-05-12 14:43:21,830   5845 [Port         ] DEB: <Dhclient count=1>: dhclient 4 is stopped: keepIpAddress=True
2023-05-12 14:43:21,831   5845 [Engine       ] INF: MgmtDhcp4Fetcher, current state:final, exit code:success: state changed to final
2023-05-12 14:43:21,832   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:final, exit code:success. Processing work: [privileged] getting engine status. done = False
2023-05-12 14:43:21,834   5845 [MgmtDhcp4Fetcher] DEB: dhcp: shutdown : Entry
2023-05-12 14:43:21,933   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:final, exit code:success. Processing work: [privileged] prepare engine shutdown. done = False
2023-05-12 14:43:22,035   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, current state:final, exit code:success. Processing work: [privileged] shutting down MgmtDhcp4Fetcher engine. done = False
2023-05-12 14:43:22,036   5845 [Engine       ] INF: MgmtDhcp4Fetcher, current state:final, exit code:shutdown
2023-05-12 14:43:22,037   5845 [Engine       ] INF: MgmtDhcp4Fetcher, exit code:shutdown: state changed to None
2023-05-12 14:43:22,038   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, exit code:shutdown: breaking engine loop after shutdown
2023-05-12 14:43:22,039   5845 [Engine       ] DEB: ZAdmin, current state:active. Processing work: Setup fetching. done = False
2023-05-12 14:43:22,039   5845 [Engine       ] DEB: MgmtDhcp4Fetcher, exit code:shutdown: end of event loop
2023-05-12 14:43:22,052   5845 [Env          ] DEB: No authentication required for Mgmt Interface
2023-05-12 14:43:22,053   5845 [Env          ] DEB: No authentication required when initiated using CLI
2023-05-12 14:43:22,055   5845 [Xr           ] DEB: Writing to file /tmp/ztp2-fzwmlfid/sysdb_cfg_cmd.tmp
2023-05-12 14:43:22,181   5845 [Xr           ] DEB: No inconsistency found in config
2023-05-12 14:43:23,460   5845 [Xr           ] DEB: Applying TPA default route
2023-05-12 14:43:23,523   5845 [Xr           ] DEB: No IPv4 Address assigned to linux management interface
2023-05-12 14:43:23,524   5845 [Xr           ] DEB: Applying IPv4 configuration
2023-05-12 14:43:23,525   5845 [Xr           ] DEB: Validating IP Address: 10.58.227.177
2023-05-12 14:43:23,527   5845 [Xr           ] DEB: Applying IPv4 gateway route configuration
2023-05-12 14:43:23,527   5845 [Xr           ] DEB: Validating DHCP server identifier IP Address: 10.58.227.11
2023-05-12 14:43:23,528   5845 [Xr           ] DEB: Validating Gateway IP Address: 10.58.227.1
2023-05-12 14:43:23,530   5845 [Xr           ] DEB: Configuring domain name with domain-name-server 198.51.100.3 198.51.100.1
2023-05-12 14:43:23,532   5845 [Configuration] DEB: Config file type is IOS XR config. Replace False
2023-05-12 14:43:23,534   5845 [Configuration] DEB: Applying following config: 
tpa
 vrf default
  address-family ipv4
   default-route mgmt
  address-family ipv6
   default-route mgmt

interface MgmtEth0/RP0/CPU0/0
no ipv4 address
ipv4 address 10.58.227.177 255.255.255.0
no shutdown

tpa
 vrf default
  address-family ipv4
   default-route mgmt
router static
 address-family ipv4 unicast
  0.0.0.0/0 10.58.227.1

domain name cisco.com

domain name-server 198.51.100.3

domain name-server 198.51.100.1

When you have a problem in the ZTP process that you cannot resolve, the resource of last resort is your Cisco Systems technical support representative. To analyze a problem, your technical support representative needs certain information about the situation and the symptoms that you are experiencing. To speed up the problem isolation and resolution process, collect the necessary data before you contact your representative.

Use the show tech-support ztp command to collect all debugging information of the ZTP process.

Example:

RP/0/RP0/CPU0:R1#show tech-support ztp
Thu Jun 15 08:33:27.531 UTC
++ Show tech start time: 2022-Jul-28.083327.UTC ++
Thu Jul 28 08:33:28 UTC 2022 Waiting for gathering to complete
..
Thu Jul 15 08:33:34 UTC 2022 Compressing show tech output
Show tech output available at 0/RP0/CPU0 : /harddisk:/showtech/showtech-R1-ZTP-2022-Jul-28.083327.UTC.tgz
++ Show tech end time: 2022-Jul-28.083334.UTC ++
RP/0/RP0/CPU0:R1#

In the above example, the tech support information is saved as .tgz file in the specified location. This information can be shared with the Cisco Technical Support representatives for troubleshooting the ZTP process.

From Release 7.10.1, you can bring up the NCS 1001 nodes that are enabled with IPv6, using the DHCP configuration file updated with dhcp6.client id and IPv6 address based bootfile URL. See IPv6 configuration file.