Check the IP address in the access switch

You can find both the IP address of an access switch and the IPs of connected devices using management interfaces, ARP/MAC tables, DHCP snooping, or network scanning tools.Finding the Switch's IP AddressManaged vs. Unmanaged Switches: Managed switches typically have a management IP for web, SSH, or SNMP access, while unmanaged switches usually do not have an IP and only forward Ethernet frames .Direct Console Access: Connect to the switch via a console cable and use commands like show ip interface brief to view IP addresses configured on VLAN interfaces, often VLAN 1 for management .Discovery Protocols: Use LLDP (Link Layer Discovery Protocol) or CDP (Cisco Discovery Protocol) from a connected device to identify the switch and its IP .DHCP Server Lookup: If the switch obtains an IP via DHCP, check the DHCP client list on your router or DHCP server for the switch's hostname or MAC address .Finding IP Addresses of Devices Connected to the SwitchMAC Address Table Lookup: On the access switch, use commands like show mac address-table to find which MAC addresses are associated with each port. Then correlate these MAC addresses with IPs using the router's ARP table (show arp) or by pinging devices .DHCP Snooping: Enable DHCP snooping on the switch to track IP addresses assigned to clients. This method works for both older and newer switch models, though newer models may also support IP client tracking (ip client-tracker) to directly list connected clients' IPs .Network Scanning Tools: Tools like Nmap or Angry IP Scanner can scan the subnet to identify all active IP addresses, which can then be matched to switch ports using MAC address tables .Recursive Tracing: For larger networks with multiple switches, start from the router or L3 switch to find the MAC address of a target IP, then trace it through the MAC address tables of connected access switches to locate the exact port .Practical TipsAlways ensure you have proper administrative access to the switch or network devices.For Layer 2 switches without IPs, you can only identify connected devices via MAC addresses and ARP tables.Combining DHCP snooping, MAC tables, and network scanning provides the most complete view of connected devices. By using these methods, you can effectively determine both the management IP of an access switch and the IP addresses of all devices connected to it, enabling better network monitoring and troubleshooting.