Customs and border protection, both components of the department of homeland security. Operation manual port security h3c s5500ei series ethernet switches chapter 1 port security configuration note that. Learn how to secure a switch port with switchport security feature step by step. Verify your configuration with port security commands in cisco ios. What i am trying to do is set the switch to only allow traffic from existing mac addresses through a port. How to configure port security sysnettech solutions. To enable portsecurity youll execute the switchport portsecurity command as previously learned in lab 419. Cisco 3845 security bundle router manual pdf download. Port security removes all secure addresses on the voice vlan of the access port. The network administrator can apply port security to dynamic access ports b.
What is port security and how does it work with my managed. This enables to keep out an unauthorised entry into the network. Switchport portsecurity securite sur les ports cisco en. Specifically, the authors of this guide used ios version 12. It enables an administrator configure individual switch ports to allow only a specified number of source mac addresses ingressing the port. You will configure port security to limit the number of mac addresses. If a packet with a valid mac address is received on a particular port then the switch will allow that packet to pass through the switching fabric of the switch as normal. Enabling port security resets the following configurations on a port to the defaults bracketed, making them dependent completely on the port security mode. Switch port configuration speed and duplex some switch interfaces are fixed at a single speed. Follow these guidelines when configuring port security. This will prevent anyone from using the port to flood unicast packets to mac addresses unknown to the switch, which helps block unauthorized users from eavesdropping on traffic intended for addresses that have already aged out of the mac.
Port security does not support switch port analyzer span destination ports. Port security capabilities are dependant on the platform allows you to specify mac addresses for each port, or to learn a certain number of mac addresses per port upon detection of an invalid mac the switch can be configured to block only the offending mac or just shut down the port port security prevents macof from flooding the cam table. Port security adds an additional layer of security to the switching network. Conventional network security often focuses more on routers and blocking traffic from the outside. Developed in collaboration with several eu ports, this report intends to provide a useful foundation on which cios and cisos of entities involved in the port ecosystem, especially port authorities and terminal operators, can build their cybersecurity strategy. That is, any device can access a port without causing a security reaction. If you reconfigure a secure trunk as an access port, port security converts all sticky and static addresses learned on the native vlan to addresses learned on the access vlan of the access port. A secure port cannot belong to an etherchannel portchannel interface. Port security does not support etherchannel port channel interfaces. You can limit the number of mac addresses on a given port. This tutorial explains switchport security modes protect, restrict and shutdown, sticky address, mac address, maximum number of hosts and switchport security violation rules in detail with examples. How to configure port security on cisco switch in gns3. Using port security, you can configure each switch port with a unique list of the mac addresses of devices that are authorized to access the network through that port. When port security is enabled on a switch, any media access control mac address not specified for that port is denied access to the switch, and to any networks to which the switch is connected.
Jul 10, 2011 enabling port security and mac sticky ports is an easy way to add some security to your network. The simplest form of switch security is using port level security. Next, by using the show port security interface fa01 we can see that the switch has learned the mac address of host a. Layer 2 managed switches can typically implement port security which consists of checking incoming packets for a matching mac address. I would suggest you to take the uplink port mac address and bind it with the port, do the same in both uplinks so that if any other mac learning on the port will be blocked or shutdown based up on your define. Packet tracer troubleshooting switch port security scenario. Often though, a single switch interface can support multiple speeds. The port security feature offers the following benefits. For example, a gigabit ethernet interface is often backwardscompatible with original and fast ethernet, and is referred to as a 10100 interface. Port security uses the vlan id configured with the switchport trunk native vlan. Basic switch commands to remember for the ccent certification.
Configuring and monitoring port security ftp directory listing. Port security is one of the methods for restricting unauthorized access to your switch ports. Port security is used to secure the port of a layer 3 switch for the purpose of to not access that port except the dedicated mac address computer, or when some violate that restriction the switch port must be off. Port security is essentially a layer 2 security mechanism that can limit the number of mac addresses that can be learned on a single switch port or perhaps be used as a security barrier to prevent anyone from unplugging a network device and plugging in a new device without authorization. By default, if a security violation occurs, the switch will shut down the offending. Port security does not support etherchannel portchannel interfaces. While the name of this feature is a bit vague, it makes it possible to limit the number and type of devices that are allowed on the. A best approach to securing a switchis to apply port security. A secure port cannot be a destination port for switch port analyzer span. The network administrator can configure static secure or sticky secure mac addresses in the. If you do not configure the port as the access mode, the switch will issue a dynamic port alert. Local law enforcement agencies and the fbi also have a role in port security at the local and regional level. The svi for vlan 99 will not appear as upup until vlan 99 is created and there is a device connected to a switch port associated with vlan 99. Finally, a security checklist for cisco switches summarizes the countermeasures.
In the apic, the user can configure the port security on switch ports. Mar 29, 2020 this article describes how to configure switch port security on cisco switches. To find evidence that port security is up and running, you would need to run the show port security interface command. Verify port security is enabled and the mac addresses of pc1 and pc2 were added to the running configuration. Create a basic switch configuration, including a name and an ip address configure passwords to ensure that access to the cli is secured configure switch port speed and duplex properties for an interface configure basic switch port security manage the mac address table assign static mac addresses.
Contremesures face aux attaques sur le reseau local. Port security is a way to limit which systems can connect to a switch. Port security can be used to block input to an ethernet, fast ethernet, or gigabit ethernet switch port. Configure port security on port fastethernet02 on sw1 so that any mac addresses learned on that interface are written to the switch s nvram. One approach is to manually configure the mac addressfor the directly connected device. It provides guidelines, procedures, and configuration examples. Cisco ccna port security and configuration switch port security limits the number of valid mac addresses allowed on a port. The total supply, or global resource, of mac addresses for the switch is 1024 mac addresses. How to enable or disable port security on a cisco switch. This is a way to limit which device can connectto a switch on a given port.
Switch and vlan security switch port security port security adds an additional layer of security to the switching network. Another approach is to automatically,or allow the switch, to automatically learnthe mac address. One of the security features available with cisco switches among other vendors is switchport security. Basic switch security concepts and configuration basic. This article describes how to configure switch port security on cisco switches. Port security helps secure the network by preventing unknown devices from forwarding packets. I am trying to confure mac address security on this powerconnect 6248 and i have some questions. I belive the switch port remember the binded mac address as long as port security is enabled. Port security is easy to configured and it allows you to secure access to a port based upon a mac address basis.
Dgs1510 series gigabit ethernet smartpro switch web ui reference guide 274 unit select the switch unit that will be used for this configuration here. In this activity, you will configure and verify port security on a switch. There are three different ways that mac addresses can be configured onto a port. By default, all interfaces on a cisco switch are turned on. State select to enable or disable the port security feature on the port s specified. In the united states, port security is handled jointly by the coast guard and u. Configuring and monitoring port security overview overview using port security, you can configure each switch port with a unique list of the mac addresses of devices that are authorized to access the network through that port. Port security allows you to restrict a port s ingress traffic by limiting the mac addresses that are allowed to send traffic into the port. See the configuring the port security violation mode on a port section on page 626 for more information about the violation modes. A network administrator needs to configure port security on a switch. To configure port security we need to access the command prompt of switch. You will configure port security to limit the number of mac addresses that can be learned on a switch port and disable the port if that number is exceeded.
Port security allows three violation modes shutdown, protect and restrict, but only the default setting of shutdown causes the switch to errdisable the interface. To do this, the interface of the port is configured as an access port with the switchport mode access command. User can either use restrict, shut down or protect. Once the mac limit has exceeded the maximum configured value on a port, all traffic from the. This means that the switch can play an important role in network security since its the entrypoint of the network. This feature enables you to configure each switch port with a unique list of the mac addresses of devices that are authorized to access. By using port security, user can limit the number of mac addresses that can be learned to a port, set static mac addresses and set penalties for that port if it is used by an unauthorised user.
Also, the mac address table gives some hints that port. By default, the maximum number of allowed mac addresses are one, so if we connect another host to the same port, the security violation will occur. Hi experts, we just deployed a new site which uses dell n2048 switches in a stack. Port security switches learn mac addresses when the frame is forwarded through a switch port. Enable portsecurity on sw1s fa01 interface and configure the interface to sticky the mac address learned. Configuring dynamic switchport security than youll be pretty much up to speed in this lab. Cisco switch port security configuration and best practices. The status code of errdisabled means that the security violation occured on. The default port security setting for each port is off. This section describes the cli port security command and how the switch acquires and maintains authorized addresses. First, it is necessary to understand the logic and importance of port security ps in cisco switches. Port security can be used to limit access on an ethernet port based on the mac address of the device to which it is connected. In our example below we will set a maximum of one mac address to be dynamically learned and in the event of a violation the port will shutdown. Lets now see the basic portsecurity configuration on cisco switches.
Cisco presentation enabling port security 2950 cisco switch the cisco catalyst 2950 series is a family of wirespeed fast ethernet desktop switches that delivers the next generation of performance and functionality for the lan with 10100baset uplinks, enhanced ios service, quality of service qos, multicast management, high availability and security features using a simple, webbased. That means that an attacker could connect to your network through a wall socket and. How to configure portsecurity on cisco switch by default there is no limit to the number of mac addresses a switch can learn on an interface and all mac addresses are allowed. Which action can you, as a port employee, undertake. Note that enabling port security on an hp procurve switch 5300xl or switch 4200vl automatically enables eavesdrop protection for that port. Sep 27, 2015 switch port security feature in switches to secure nework limit the number of devices on switch ports uses mac addresses for limitations 10.
Port security can also configured locally and has no mechanism for controlling port security in a centralized fashion for distributed switches. Figure 1 shows a serial line terminal server and separate management host for outofband console port access to all switches. Switches can be subject to mac address table overflow attacks, mac spoofing attacks, and unauthorized connections to switch ports. How to configure switch port security on cisco switches. If we want we can change this behavior with port security. The implications and reasoning behind this action are explained in the next chapter. How to configure port security on cisco switch by default there is no limit to the number of mac addresses a switch can learn on an interface and all mac addresses are allowed. When using port level security, the mac addresses andor number of mac addresses of the connected devices is controlled. Port security is enabled per port and the switch port will only allow traffic from the learned mac address to be forwarded. Basic switching concepts and configuration 25 address 172.
Port cybersecurity good practices for cybersecurity in. Using the show port security interface fa01 command on sw1, we can see that the switch has learned the mac address of host a. If you are using a cisco switch on a network, we recommend that you enable port security on devices for network security. By default, the maximum number of allowed mac addresses is one. One of the best practices in network security is to try and stop security threats from the entrypoint of a lan network. When configuring the security for a network, it is important to take advantage of the security features of all deployed devices. Configure port security on individual fastethernet ports. By configuring port security you can make sure that only certain mac addresses are allowed to connect to certain switch ports and if others are detected, these ports can be shutdown.
Types of port security port security with dynamic mac addresses port security with static mac addresses port security with sticky mac addresses 11. Anyone can access unsecure network resources by simply. How to configure switch port security in packet tracer. This enables individual ports to detect, prevent, and log attempts by unauthorized devices to communicate through the. Trying to set mac address port security to a switch dell. How to configure switchport security example switchport security makes it possible to limit the number and type of devices that are allowed on the individual switchports. However, a best practice for basic switch configuration is to change the management vlan to a vlan other than vlan 1. Cisco ios switch security configuration guide csirt gov.
A secure port and static mac address configuration are mutually exclusive. Its called port security and you can use it to limit the number of mac addresses per interface or even to specify which mac address can connect to each physical port of the switch. How to configure port security mac sticky on cisco switches. This enables individual ports to detect, prevent, and log attempts by unauthorized devices to communicate through the switch. View and download cisco 3845 security bundle router manual online.
Port security supports access and trunking etherchannel port channel interfaces. The study lists the main threats posing risks to the port ecosystem and describes key cyberattack scenarios that. To adjust the maximum number of allowed vlans, up to 1024. If a specific host will always remain connected to a specific switch port, then the switch can filter all other mac addresses on that port using port security. Packets that have a matching mac address secure packets are forwarded. Aruba 3810 5400r management and configuration guide for. Dynamic port security is great but what about when you connect switches to routers or other devices that need to be secured in a way to prevent unauthorized device swapping in the network. From port to port select the appropriate port range used for the configuration here. We would now like to add port security to the switch, port mac locking to lockdown a port if another computer is connected.
From privilege exec mode use configure terminal command to enter in global configuration mode. What is port security and how does it work with my managed switch. Were are done with port security configuration for fa01. Port security supports access and trunking etherchannel portchannel interfaces. Apart from switchport port security is there any way that pcs should not move from one port to another, becz i am using dot1x on the port and switchport port security is not supported with dot1x as per cisco recommends that we should not use both features on one port. Configuring sticky switchport security free ccna workbook. Enable the port and verify that rogue laptop can ping pc1 and pc2.
In part 4, you will shut down unused ports, turn off certain services running on the switch, and configure port security based on mac addresses. After reminding him of the security policy that does not allow personal devices on the network, you now must reconnect pc1 and reenable the. The employee who normally uses pc1 brought his laptop from home, disconnected pc1 and connected the laptop to the telecommunication outlet. Backgroundpreparation cable a network similar to the one in the diagram. Configuring dynamic switchport security free ccna workbook. Chapter 261 catalyst 6500 series switch cisco ios software configuration guiderelease 12. This code example uses a sticky mac address that tells the switch to configure the port for whatever. Moving on in a similar way to switch interface fa01, configure switch port security for fa02 connected to pc2. Consider what happens if we connect a different host to the same port. It also can be used to limit the total number of devices plugged into a switch port, thereby protecting the switch from a mac flooding attack as well as reducing the risks of rogue wireless access points or hubs. When a mac address, or a group of mac addresses are configured to enable switch port security, the switch will forward packets only to the devices using those mac addresses.
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