Telnet Custom Port

Telnet connection test with custom port configuration. Tests that telnet server correctly uses the configured port and rejects connections on the default port when a custom port is configured.

Telnet Connection Failure on Default Port

Description

Telnet connection should fail on default port 23 when DUT0 is configured for port 3100

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.215.168.20/24
set service telnet port 3100
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 address 10.215.168.21/24
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Ping IP address 10.215.168.20 from DUT1:

admin@DUT1$ ping 10.215.168.20 count 1 size 56 timeout 1

Show output

PING 10.215.168.20 (10.215.168.20) 56(84) bytes of data.
64 bytes from 10.215.168.20: icmp_seq=1 ttl=64 time=0.797 ms

--- 10.215.168.20 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.797/0.797/0.797/0.000 ms

Step 4: Init a Telnet connection from DUT1 to IP address 10.215.168.20 which is going to fail:

admin@DUT1$ telnet 10.215.168.20

Show output

Trying 10.215.168.20...
telnet: Unable to connect to remote host: Connection refused
  CLI Error: Command error
admin@osdx$

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Telnet Connection Success on Custom Port

Description

Telnet connection should succeed on custom port 3100 when DUT0 is configured for port 3100

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.215.168.20/24
set service telnet port 3100
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 address 10.215.168.21/24
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Ping IP address 10.215.168.20 from DUT1:

admin@DUT1$ ping 10.215.168.20 count 1 size 56 timeout 1

Show output

PING 10.215.168.20 (10.215.168.20) 56(84) bytes of data.
64 bytes from 10.215.168.20: icmp_seq=1 ttl=64 time=0.370 ms

--- 10.215.168.20 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.370/0.370/0.370/0.000 ms

Step 4: Init a Telnet connection from DUT1 to IP address 10.215.168.20 using port 3100 :

admin@DUT1$ telnet 10.215.168.20 port 3100

Show output

Trying 10.215.168.20...
Connected to 10.215.168.20.
Escape character is '^]'.

Linux 6.1.158 (osdx) (pts/0)

osdx login:
Password:

Welcome to Teldat OSDx v4.2.8.2

This system includes free software.
Contact Teldat for licenses information and source code.

Last login: Tue Jan 27 12:49:09 UTC 2026 from 10.215.168.21 on pts/0
admin@osdx$

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