Red Hat Ansible for Network Automation

Add a variable to the network group variables file to support template-driven configuration that enables SNMP. Add another variable, named ro_community, and set the value of this variable to redhat. The updated group_vars/network/vars.yml variable file should have the following content:

ansible_connection: network_cli
domain_name: lab.example.com
nameservers:
- 8.8.8.8
- 8.8.4.4
syslog_ipv4: 172.25.250.254
ro_community: redhat
snmp_clients:
- 172.25.250.254
- 172.25.250.9

Update NOS-specific device configuration templates to provide parameterized configuration statements that enable SNMP.

1. Add a line to the device configuration Jinja2 template for VyOS devices. It should map appropriate variables to the VyOS statements that enable SNMP. The updated j2/vyos-config.j2 template should have the following content:

   set system host-name {{ inventory_hostname }}
   set system domain-name {{ domain_name }}
   {% for nameserver in nameservers %}
   set system name-server {{ nameserver }}
   {% endfor %}
   set system syslog host {{ syslog_ipv4 }} facility local7 level {{ vyos_loglevel }}
   set service snmp community {{ ro_community }} authorization ro
   {% for snmp_client in snmp_clients %}
   set service snmp community {{ ro_community }} client {{ snmp_client }}
   {% endfor %}

2. Add lines to the device configuration Jinja2 template for IOS devices. It should map appropriate variables to the IOS statements that enable SNMP. The updated j2/ios-config.j2 template should have the following content:

   hostname {{ inventory_hostname }}
   ip domain-name {{ domain_name }}
   {% for nameserver in nameservers %}
   ip name-server {{ nameserver }}
   {% endfor %}
   service timestamps log datetime
   service timestamps debug datetime
   logging {{ syslog_ipv4 }}
   logging trap {{ ios_loglevel }}
   access-list 1 permit {{ workstation_ipv4 | ipaddr('address') }} log
   access-list 1 permit {{ tower_ipv4 | ipaddr('address') }} log
   snmp-server community {{ ro_community }} RO 1

   Note

   The snmp-server command only supports standard access lists.

Perform a multivendor play that configures network devices from the updated Jinja2 templates.

1. Perform the play found in the j2cfg.yml file. You already created the j2cfg.yml playbook, which sources configuration statements from the VyOS and IOS Jinja2 templates.

   [student@workstation proj]$ ansible-playbook j2cfg.yml

2. Install the SNMP network management utilities on workstation.

   [student@workstation proj]$ sudo yum install net-snmp-utils

3. Verify that SNMP is now enabled and working properly. On workstation, run snmpwalk using the read-only community string you defined (redhat). Filter the results based on the pattern sysName.

   [student@workstation proj]$ snmpwalk -v1 -c redhat spine01 sysName
   SNMPv2-MIB::sysName.0 = STRING: spine01
   [student@workstation proj]$ snmpwalk -v1 -c redhat spine02 sysName
   SNMPv2-MIB::sysName.0 = STRING: spine02
   [student@workstation proj]$ snmpwalk -v1 -c redhat leaf01 sysName
   SNMPv2-MIB::sysName.0 = STRING: leaf01
   [student@workstation proj]$ snmpwalk -v1 -c redhat leaf02 sysName
   SNMPv2-MIB::sysName.0 = STRING: leaf02
   [student@workstation proj]$ snmpwalk -v1 -c redhat cs01 sysName
   SNMPv2-MIB::sysName.0 = STRING: cs01.lab.example.com