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Trunk and Access Link between Switches

As shown on the topology below, I have 2 Cisco Switches linked together.
I have R3 and R4 configured as hosts with No IP Routing command.
I can ping from R3 to R4  and back.
Initially I thought a link between 2 switches is always a Trunk, but I do not see a Trunk formed between Switch1 and Switch2:

User generated image
Switch1#sh interfaces fastEthernet 1/1 trunk

Port      Mode         Encapsulation  Status        Native vlan
Fa1/1     off          802.1q         not-trunking  1

Port      Vlans allowed on trunk
Fa1/1     1

Port      Vlans allowed and active in management domain
Fa1/1     1

Port      Vlans in spanning tree forwarding state and not pruned
Fa1/1     1
Switch1#

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Switch2#show interfaces fastEthernet 1/0 trunk

Port      Mode         Encapsulation  Status        Native vlan
Fa1/0     off          802.1q         not-trunking  1

Port      Vlans allowed on trunk
Fa1/0     1

Port      Vlans allowed and active in management domain
Fa1/0     1

Port      Vlans in spanning tree forwarding state and not pruned
Fa1/0     1
Switch2#

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Correct I am using Switch 3700 with slot NM-16ESW on GNS3
So when I linked the switches , will their ports be Access ports but in the same Vlan 1 ?
I can ping between R3 and R4 and back, so thy got to be in the same Vlan:

Switch1#sh interface fastEthernet 1/1 switchport
Name: Fa1/1
Switchport: Enabled
Administrative Mode: static access
Operational Mode: static access
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
Negotiation of Trunking: Disabled
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Trunking VLANs Enabled: ALL
Trunking VLANs Active: 1
Priority for untagged frames: 0
Override vlan tag priority: FALSE
Voice VLAN: none
Appliance trust: none
Switch1#

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Switch2#sh interfaces fastEthernet 1/0 switchport
Name: Fa1/0
Switchport: Enabled
Administrative Mode: static access
Operational Mode: static access
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
Negotiation of Trunking: Disabled
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Trunking VLANs Enabled: ALL
Trunking VLANs Active: 1
Priority for untagged frames: 0
Override vlan tag priority: FALSE
Voice VLAN: none
Appliance trust: none
Switch2#

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Switch1(config-if)#switchport mode ?
  access  Set trunking mode to ACCESS unconditionally
  trunk   Set trunking mode to TRUNK unconditionally

I believe the Switch simulator on GNS3 does not have the mode dynamic desirable for an interface..

Regarding Packet Tracer 6.1.1, it has this command:
Switch(config-if)#switchport mode dynamic ?
  auto       Set trunking mode dynamic negotiation parameter to AUTO
  desirable  Set trunking mode dynamic negotiation parameter to DESIRABLE

 but Packet Tracer  lacks other commands that the simulated Switch on GNS3 has.
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Thank you Guys!!