The Telenegar Port Check Tool is a network security utility designed to test whether specific TCP ports are open, filtered, or closed on a target IPv4 address.

It helps systems administrators, network engineers, and security teams verify server connectivity, audit firewall configurations, confirm service accessibility, and detect unauthorized open ports.

The Port Check interface provides organized category presets and probe selection options to streamline service auditing:

The tool categorizes standard network services into collapsible presets for quick selection:

# **Enter Target IPv4 Address:** Type the destination IPv4 address into the **TARGET IPV4 ADDRESS** field (e.g., ''216.239.38.120'').
# **Select Target Port:** Click on a service category (e.g., **Mail**, **Oracle**, or **Other**) to expand the list, then select the radio button for the desired service preset.
# **Select Probe Location:** Choose a remote probe from the **PROBE** dropdown menu (e.g., ''Falkenstein, Germany — Hetzner Online GmbH'') to test reachability from that location.
# **Execute Check:** Click the blue **Check Port** button to attempt a TCP connection. Use the **Clear** button to reset selected inputs.

Verify whether edge firewalls or security group rules correctly restrict external access to database ports (e.g., MySQL `3306`, MSSQL `1433`), directory services (`LDAP`/`LDAPS`), or enterprise application suites (`WebLogic`).

Validate client access and mail transfer ports (`25`, `465`, `587`, `993`) before configuring Mail Clients or enforcing MTA-STS.

• *For automated SPF, DKIM, and DMARC auditing, use the Telenegar Mail Check Tool.*

Audit accessibility for WebLogic application servers (`7001`/`7002`), administration portals (`9001`), and database listeners (`1521`/`2484`) across hybrid infrastructure.

If a host responds to a Ping Check but fails a Port Check, the host is online, but the target daemon is either stopped or blocked by a firewall rule.

• Telenegar Ping Check Tool — Test IP reachability, ICMP response, and packet latency.
• Telenegar Site Check Tool — Audit website availability, HTTP status codes, and SSL/TLS certificates.
• Telenegar Mail Check Tool — Diagnostic tool for email authentication and security protocols.
• Telenegar Subnet Calculator Tool — Compute IPv4 subnets, address ranges, and wildcard masks.
• Cybersecurity Best Practices — Network perimeter defense and service hardening guidelines.