An administrator is unable to connect to a server via VNC. Upon investigating the host firewall configuration, the administrator sees the following lines: - A INPUT -m state --state NEW -m tcp -p…

Question

Options

• ADENY needs to be changed to ACCEPT on one line.
• BA line needs to be added.
• CA line needs to be removed.
• DFix the typo in one line.

• A
  22% (12)
• B
  59% (32)
• C
  13% (7)
• D
  6% (3)

Explanation

VNC uses TCP port 5900 (or 5901+) by default. Reviewing the existing firewall rules: port 3389 (RDP) is denied, port 22 (SSH) is denied, port 10000 is accepted, port 80 is denied, and there is an inbound ACCEPT for source port 3389 (which is misconfigured but irrelevant to VNC). There is no rule that permits inbound traffic on port 5900 (VNC). Since the implicit default policy denies unmatched traffic, VNC connections are silently dropped. The fix is to add a new rule: '-A INPUT -m state --state NEW -m tcp -p tcp --dport 5900 -j ACCEPT'. No existing rule needs to be changed (A is wrong), removed (C is wrong), or typo-corrected (D is wrong)-the VNC port rule simply does not exist yet.

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