Managing Switch with Ansible Via SSH

[sleepless swan]

I am trying to manage a Catalyst 2960 switch with Ansible. The ansible controller is installed on a Linux VM. I haven't been able to SSH to the switch from the controller despite the service being enabled on the switch and the controller. 

Connection:

- PC connected to switch with an ethernet cable. The port is configured with an IP in the same subnet as the VM. 

Switch configuration

version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname ansible
!
boot-start-marker
boot-end-marker
!
!
username mikko privilege 15 password 0 P@ssw0rd
username pocha privilege 15 secret 5 $1$OgQZ$HheCqdqxYg5az5KEaTrNV.
no aaa new-model
system mtu routing 1500
ip subnet-zero
!
ip domain-name ansible.bh
!
!
!
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
ip ssh version 1
!
!
interface FastEthernet0/1
 switchport mode access
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
 ip address 192.168.7.17 255.255.255.0
 no ip route-cache
!
ip http server
ip http secure-server
!
control-plane
!
!
line con 0
line vty 0 4
 login local
 transport input ssh
line vty 5 15
 login local
 transport input ssh
!
end

Whenever I try to ssh to the switch from the vm, I get a 'no route to host' error. Pinging gives a destination unreachable error.

I've tried to ssh to the switch using Putty, but the connection timed out. 

Is it actually possible to manage the switch using Ansible with the current setup? 

[liviu.gheorghe]

Hello @sleepless swan ,

the switch configuration looks ok and you should be able to ssh into it, provided your PC has an IP from the 192.168.7.0/24 subnet and you have generated the rsa key needed for ssh.

You are trying to access the switch from a VM which is hosted on virtualisation platform, HyperV or ESXi for example. How is the virtualisation host connected to the switch? On interface FastEthernet 0/1?

How is the vSwitch from the virtualisation host configured? Trunk or single vlan?

[sleepless swan]

Hello @liviu.gheorghe

Indeed both the switch and VM are in the same subnet.

I'm using VirtualBox. The network adapter for the VM is set to NAT with the same subnet as the switch. The pc is connected to the fastethernet 0/1 port on the switch with an ethernet cable. I also have serial connection to the switch for direct configuration. 

Is it possible that I should choose the bridged network adapter for the VM instead? I still haven't tested that yet because it would require a VM reboot and it would take quite sometime due to the tools running on the VM.

[bigevilbeard]

I see no reason for this not to work here.

• Double-check IP addresses: Ensure the VM and switch are configured with valid IP addresses in the same subnet.
• Check subnet mask: Confirm both devices have the same subnet mask (e.g., 255.255.255.0).
• Verify default gateway: Make sure the VM has the switch's IP address set as its default gateway.
• Check the routing table on the PC connected

Hope this helps.

[Georg Pauwen]

Hello,

is there a specific reason you are using SSH v1 ? Can you ping 192.168.7.17 from the Ansible controller ?

[sleepless swan]

I'm assuming it wouldn't matter if it's v1 since it's just a testing environment? Unfortunately, I'm unable to ping from the Ansible controller which of course means I can't SSH to it. 

[liviu.gheorghe]

Can you share the output of the netstat -nr command from the linux vm?

[sleepless swan]

Hello @liviu.gheorghe 

Please find the requested output

[liviu.gheorghe]

And also show arp from the switch and arp -an from the linux vm.

[sleepless swan]

[liviu.gheorghe]

Also show cdp neighbor from the switch.

You have no communication between your switch and the linux vm - no Mac address of the vm or switch in each others arp table.

Your linux VM is hosted on what virtualisation platform? Vmware, HyperV or something else?

[sleepless swan]

There are no cdp neighbors in the output. I'm using VirtualBox

[liviu.gheorghe]

Ok. Then I believe there is a problem with the networking configuration on your VirtualBox. Can you share a screenshot of the networking configuration for the linux vm?

[sleepless swan]

These are the NAT adapter settings

[liviu.gheorghe]

I would change the settings for the first adapter - Attached to: Bridged Adapter.

This way you are sure that your vm is in the same vlan as the switch management vlan. I presume that the PC you are running VirtualBox on is attached to the switch on the first port - interface FastEthernet0/1.