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Zorluk: ZorSSH Secure Remote Access Configuration and Verification

An engineer is configuring secure remote management on a central router named Edge-Rtr1. The device has a valid hostname, an IP domain name configured, a 1024-bit RSA key pair generated, and a local administrator user defined in global configuration mode. The virtual terminal lines are configured with transport input ssh. However, when connecting via SSH from a remote client, the router prompts only for a password instead of requesting a username, causing all login attempts to fail. Which configuration change on Edge-Rtr1 resolves this issue?

  1. Apply the login local command under line vty configuration mode.Cevap
  2. B
    Regenerate the RSA key pair using a minimum modulus length of 2048 bits.
  3. C
    Add an explicit permit statement to the implicit deny clause on the VTY lines.
  4. D
    Configure ip ssh version 1 in global configuration mode to enable single-factor password prompts.

Cevap

Apply the login local command under line vty configuration mode to instruct the switch/router to authenticate against the local user database.
The correct answer specifies applying the 'login local' command under line vty configuration mode. When SSH is enabled, Cisco IOS requires an authentication source capable of verifying usernames and passwords. Standard 'login' only checks for a single line-level password. Applying 'login local' directs the VTY lines to validate incoming credentials against usernames created in the local database.

Adım Adım Çözüm

1
Analyze the reported authentication symptom
The router prompts only for a password without asking for a username.
By default, line vty uses standard line authentication ('login'), which expects a password configured directly on the line via the 'password' command rather than searching local user accounts.
2
Determine the required VTY configuration command
Adding 'login local' under line vty 0 4 binds authentication to the local running-config database.
SSH requires username-based authentication. Without 'login local' (or AAA), the VTY lines cannot process the username sent by the SSH client.

Anahtar Kavram

VTY Line Local Authentication Binding for SSH
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