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How to Configure Redhat 7 & 8 Network Interfaces using Ansible

| October 10, 2022
• This role will configure redhat 7 and up interfaces for virtual and physical.
(bonded nics, gateways, routes, interface names)

How to use this role:

1.You must first download the git repository into your roles directory usually ansible/role/
2.Now you want edit the hosts.client file name file or create it if it doesn’t exist under your “ansible/inventory/dev:staging:prod” directory. This is a good way to separate environments with ansible, inside each environment you should have a hosts.file like indicated below.

Example file: hosts.dev, hosts.staging, hosts.prod

c.Put your server under the appropriate group inside the file and save
d.testmachine1 ansible_host=192.168.1.101

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Cool Stuff: If you deployed a virtual-machine using the ansible-vmware modules it will set the hostname of the host using the same shortname of the vm. If you require the fqdn vs the shortname on the host. To solve this I added some code to set the fdqn as the new_hostname if you define it under you hosts.file as shown below.

e.testmachine1 ansible_host=192.168.1.101 new_hostname=testmachine1.nicktailor.com

.

Now inside this directory you should see hosts & host_vars, group_vars

Descriptions:

f.Hosts. – is where you will list your servers under specific groups which tell the playbook (what the server is, if it the server should have a specific task run on it, and how to find it)
g.Host_vars – Inside this directory is where you list the server by name which is you will list under hosts. Inside these files you pass variable parameters to the specific roles when running your playbook. Without these the playbook cant do the tasks you want it to.
h.Group_vars – Are how a way to group variables for sets of servers and this keeps code cleaners and easier to manage.

Operational Use:

3.Move inside host_var
i.cd host_var
j.create a file called {{ servername }} and save it for us its testmachine1.nicktailor.com

.

4.Now inside this directory you should see hosts & host_vars, group_vars

Descriptions:

k.Hosts. – is where you will list your servers under specific groups which tell the playbook (what the server is, if it the server should have a specific task run on it, and how to find it)
l.Host_vars – Inside this directory is where you list the server by name which is you will list under hosts. Inside these files you pass variable parameters to the specific roles when running your playbook. Without these the playbook cant do the tasks you want it to.
m.Group_vars – Are how a way to group variables for sets of servers and this keeps code cleaners and easier to manage.

Operational Use:

5.Move inside host_var
n.cd host_var
o.create a file called {{ servername }} and save it for us its testmachine1.nicktailor.com
p.add the following parameters to your inventory file and save.

passed parameters: example: var/testmachine1

#Configure network can be used on physical and virtual-machines

nic_devices:

    – device: ens192

      ip: 192.168.10.100

      nm: 255.255.255.0

      gw: 192.168.10.254

      uuid:

      mac:

..

Note: you do not need to specify the UUID, you can if you wish. You do need the MAC. if you are doing bonded nics on the hosts. If you are using physical machines with satellite deployments. Then its probably a good to idea to use the mac of the nic you want the dhcp request to hit to avoid accidently deploying to the wrong host. When dealing with physical machines you don’t really have the same forgiveness of snapshots or quickly rebuilding as a vm. You can do more complicated configurations as indicated below….You can always email or contact me via linkedin, top right of the blog if you need assistance.

More Advanced configurations: bonded nics, routes, multiple nics and gateways

bond_devices:

    – device: ens1

      mac: ec:0d:9a:05:3b:f0

      master: mgt

      eth_opts: ‘-C ${DEVICE} adaptive-rx off rx-usecs 0 rx-frames 0; -K ${DEVICE} lro off’

    – device: ens1d1

      mac: ec:0d:9a:05:3b:f1

      master: mgt

      eth_opts: ‘-C ${DEVICE} adaptive-rx off rx-usecs 0 rx-frames 0; -K ${DEVICE} lro off’

    – device: mgt

      ip: 10.100.1.2

      nm: 255.255.255.0

      gw: 10.100.1.254

      pr: ens1

    – device: ens6

      mac: ec:0d:9a:05:16:g0

      master: app

    – device: ens6d1

      mac: ec:0d:9a:05:16:g1

      master: app

    – device: app

      ip: 10.101.1.3

      nm: 255.255.255.0

      pr: ens6

routes:

    – device: app

      route:

        – 100.240.136.0/24

        – 100.240.138.0/24

.

    – device: app

      gw: 10.156.177.1

      route:

        – 10.156.148.0/24

.

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Running your playbook:

1.You must run your play book from inside parent directory always “ansible”
2.Now there is a playbook called setup-networkonly.yml in the ansible directory which simply calls the setup-redhat-interfaces role inside the roles directory.

Example: of ansible/ setup-networkonly.yml

– hosts: all

  gather_facts: no

  roles:

   – role: setup-redhat-interfaces

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Command:

ansible-playbook -i inventory/dev/hosts setup-networkonly.yml–limit=’testmachine1.nicktailor.com’

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• -i : This flag tells ansibe-playbook command which hosts file to use, these are always defined by environment like hosts.dev or hosts.staging
• -u : this is the ssh_user you will be connecting to the servers with
• -Kkb : this tells ansible that you will be using sudo su – for the ssh_user when running all role/tasks
• -ask-beocme : is saying become root
• -limit=’server’ : this allows you to segement which server you want to run the playbook against.

.

.

Test Run:

[root@ansible-home]# ansible-playbook –i inventory/dev/hosts setup-metworkonly.yml –limit=’testmachine1.nicktailor.com’ -k

SSH password:

.

PLAY [all] *************************************************************************************************************************************************************************

.

TASK [setup-redhat-network : Gather facts] ************************************************************************************************************************************

ok: [testmachine1.nicktailor.com]

.

TASK [setup-redhat-network : set_fact] ****************************************************************************************************************************************

ok: [testmachine1.nicktailor.com]

.

TASK [setup-redhat-network : Cleanup network confguration] ********************************************************************************************************************

ok: [testmachine1.nicktailor.com]

.

TASK [setup-redhat-network : find] ********************************************************************************************************************************************

ok: [testmachine1.nicktailor.com]

.

TASK [setup-redhat-network : file] ********************************************************************************************************************************************

changed: [testmachine1.nicktailor.com] => (item={u’rusr‘: True, u’uid‘: 0, u’rgrp‘: True, u’xoth‘: False, u’islnk‘: False, u’woth‘: False, u’nlink‘: 1, u’issock‘: False, u’mtime‘: 1530272815.953706, u’gr_name‘: u’root‘, u’path‘: u’/etc/sysconfig/network-scripts/ifcfg-enp0s3′, u’xusr‘: False, u’atime‘: 1665494779.63, u’inode‘: 1055173, u’isgid‘: False, u’size‘: 285, u’isdir‘: False, u’ctime‘: 1530272816.3037066, u’isblk‘: False, u’wgrp‘: False, u’xgrp‘: False, u’isuid‘: False, u’dev‘: 64769, u’roth‘: True, u’isreg‘: True, u’isfifo‘: False, u’mode‘: u’0644′, u’pw_name‘: u’root‘, u’gid‘: 0, u’ischr‘: False, u’wusr‘: True})

changed: [testmachine1.nicktailor.com] => (item={u’rusr‘: True, u’uid‘: 0, u’rgrp‘: True, u’xoth‘: False, u’islnk‘: False, u’woth‘: False, u’nlink‘: 1, u’issock‘: False, u’mtime‘: 1530272848.538762, u’gr_name‘: u’root‘, u’path‘: u’/etc/sysconfig/network-scripts/ifcfg-enp0s8′, u’xusr‘: False, u’atime‘: 1665494779.846, u’inode‘: 2769059, u’isgid‘: False, u’size‘: 203, u’isdir‘: False, u’ctime‘: 1530272848.6417623, u’isblk‘: False, u’wgrp‘: False, u’xgrp‘: False, u’isuid‘: False, u’dev‘: 64769, u’roth‘: True, u’isreg‘: True, u’isfifo‘: False, u’mode‘: u’0644′, u’pw_name‘: u’root‘, u’gid‘: 0, u’ischr‘: False, u’wusr‘: True})

.

TASK [setup-redhat-network : file] ********************************************************************************************************************************************

ok: [testmachine1.nicktailor.com]

.

TASK [setup-redhat-network : Setup bond devices] ******************************************************************************************************************************

changed: [testmachine1.nicktailor.com] => (item={u’device‘: u’enp0s8′, u’mac‘: u’08:00:27:13:b2:73′, u’master‘: u’mgt‘})

changed: [testmachine1.nicktailor.com] => (item={u’device‘: u’enp0s9′, u’mac‘: u’08:00:27:e8:cf:cd’, u’master‘: u’mgt‘})

changed: [testmachine1.nicktailor.com] => (item={u’device‘: u’mgt‘, u’ip‘: u’192.168.10.200‘, u’nm‘: u’255.255.255.0′, u’gw‘: u’10.0.2.2′, u’pr‘: u’enp0s8′})

.

TASK [setup-redhat-network : Setup NIC] ***************************************************************************************************************************************

.

TASK [setup-redhat-network : Setup static routes] *****************************************************************************************************************************

.

PLAY RECAP *************************************************************************************************************************************************************************

testmachine1.nicktailor.com : ok=7    changed=2    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0

.

[root@testmachine1.nicktailor.com]# cat /proc/net/bonding/mgt

Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

.

Bonding Mode: fault-tolerance (active-backup)

Primary Slave: enp0s8 (primary_reselect failure)

Currently Active Slave: enp0s8

MII Status: up

MII Polling Interval (ms): 100

Up Delay (ms): 0

Down Delay (ms): 0

.

Slave Interface: enp0s8

MII Status: up

Speed: 1000 Mbps

Duplex: full

Link Failure Count: 0

Permanent HW addr: 08:00:27:13:b2:73

Slave queue ID: 0

.

Slave Interface: enp0s9

MII Status: up

Speed: 1000 Mbps

Duplex: full

Link Failure Count: 0

Permanent HW addr: 08:00:27:e8:cf:cd

Slave queue ID: 0

.

[root@testmachine1.nicktailor.com]# ip a

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000

    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

    inet 127.0.0.1/8 scope host lo

       valid_lft forever preferred_lft forever

    inet6 ::1/128 scope host

       valid_lft forever preferred_lft forever

2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000

    link/ether 08:00:27:63:63:0e brd ff:ff:ff:ff:ff:ff

    inet 10.0.2.15/24 brd 10.0.2.255 scope global noprefixroute dynamic enp0s3

       valid_lft 86074sec preferred_lft 86074sec

    inet6 fe80::a162:1b49:98b7:6c54/64 scope link noprefixroute

       valid_lft forever preferred_lft forever

3: enp0s8: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master mgt state UP group default qlen 1000

    link/ether 08:00:27:13:b2:73 brd ff:ff:ff:ff:ff:ff

4: enp0s9: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master mgt state UP group default qlen 1000

    link/ether 08:00:27:13:b2:73 brd ff:ff:ff:ff:ff:ff

5: enp0s10: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000

    link/ether 08:00:27:05:b4:e8 brd ff:ff:ff:ff:ff:ff

6: bond0: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noop state DOWN group default qlen 1000

    link/ether ae:db:dc:52:22:f8 brd ff:ff:ff:ff:ff:ff

7: mgt: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000

    link/ether 08:00:27:13:b2:73 brd ff:ff:ff:ff:ff:ff

    inet 192.168.10.200/24 brd 192.168.56.255 scope global mgt

       valid_lft forever preferred_lft forever

    inet6 fe80::a00:27ff:fe13:b273/64 scope link

       valid_lft forever preferred_lft forever

.

October 10, 2022 Ansible, Linux, Network StuffNo Comments »

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