To display port security settings for the switch or for the specified interface, use the show port security interface interfaceid command. The output for the dynamic port security configuration is shown in the example below. Once the mac limit has exceeded the maximum configured value on a port, all traffic from the. Basically the same as if you had a pc connected to one port with say vlan x and your voip phone connected to another port with say vlan y. Security configuration guide, cisco ios release 15. Cisco switch port security best cisco ccna ccnp and. Catalyst cisco s flagship switching platform, with a large selection of models spanning access, distribution, and core layers. First, the switch loads a poweron selftest post program stored in rom. Layer 2 switch security technical implementation guide cisco. The following example shows the configuration of port security on a cisco switch. The best advise is to follow this video through, then some other settings to see how it reacts. View and download cisco 3845 security bundle router manual online. Port security can use dynamically learned sticky mac addresses to facilitate the initial configuration. Learn how to secure a switch port with switchport security feature step by step.
Sample configuration files for two different models of cisco switches are included that combine most of the countermeasures in this guide. Next, by using the show portsecurity interface fa01 we can see that the switch has learned the mac address of host a. Learn the basics of port security, and find out how to configure this feature. Switch security overview in the video tutorials below, i show how to use packet tracer to build a small lan with a cisco 2960 switch, three pc clients, and two pc servers, one of the servers is placed on a separate vlan for management purposes. How to configure port security on a cisco switch youtube. It provides guidelines, procedures, and configuration examples. How to configure switch port security on cisco switches. Verify port security background in this activity, you will configure and verify port security on a switch. Switch port security configuration on cisco packet tracer.
Port security is one of the methods for restricting unauthorized access to your switch ports. A security violation occurs if the maximum number of secure mac addresses has been added to the address table and a workstation whose mac address is not in the address table attempts to access the interface. 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. Cisco ccna port security and configuration switch port security limits the number of valid mac addresses allowed on a port. May 06, 2007 port security configuration guidelines. The following sections describe how to configure port security. Enable port security on sw1 interface fa01 and allow a maximum of 3 mac addresses. Port trunking must be disabled on all access ports do not configure trunk on, desirable, nonnegotiate, or autoonly off. Cisco switch port security packet tracer demonstration part. Nexus highend switches focused at datacenter environments. Port security is a topic on the ccent exam and its important to know what it is and how to configure it. All meraki switches are managed through an elegant, intuitive cloudbased interface, rather than cryptic command line.
The continue reading basic switch configuration and port security. Layer 2 interfaces on a cisco switch are referred to as ports. To practice and learn to configure port security on cisco switch, just download the port security packet tracer lab or create your own lab and follow the switch port security configuration guideline. Configure the active ports to allow a maximum of 4 mac addresses to be learned on the ports. 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. This includes adjusting port speed, bandwidth and security requirements. Today i will discuss about cisco switch port security issue. Activate port security on all the active access ports on switch sw1. Catalyst 2960 switch software configuration guide cisco. Catalyst 4500 series switch cisco ios software configuration. Switchport security is not supported on switch port analyzer span destination ports. The configuration shown in table 5 will enable the use of the switchport security feature on ports f01 and f02, statically configure the 0000. If you do not configure the port as the access mode, the switch will issue a dynamic port.
In this topology we will make examples for the configuration cases on port security. Port security does not support etherchannel portchannel interfaces. In the apic, the user can configure the port security on switch ports. Basic switch configuration and port security danscourses. The following commands will work on most cisco switch models such as 4500, 3850, 3650, 2960, 3560 etc. The switch port must be an access port else we cannot apply switch port security on that port.
Port security supports access and trunking etherchannel portchannel interfaces. 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. All cisco meraki switches are managed through an elegant, intuitive cloud interface, rather than a cryptic command line. Cisco 3845 security bundle router manual pdf download.
Port security must be configured for all cisco switches to be installed to limits the number of valid mac addresses allowed on a port. Catalyst 4500 series switch cisco ios software configuration guide, 12. When a mac address, or a group of mac addresses are configured to enable switch port security, the switch will forward packets only to. Knowing the victims mac address and with the victim attached to. Switch and vlan security switch port security port security adds an additional layer of security to the switching network. Switch port configuration cisco operating systems cisco offers two brands of network switches. One of the most overlooked security areas is the configuration of individual switchport security configuration. By default, there is one mac address allowed on this port.
The mac address of a host generally does not change. In this activity, you will configure and verify port security on a switch. Use show port security interface to see the port security details per interface. Hello, the router is unable to assign ip address to the 192. Port security is used to mitigate mac address spoofing at the access interface. For our port security configuration, we will use the below topology. Port security allows you to restrict a ports ingress traffic by limiting the mac addresses that are allowed to send traffic into the port. 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. Port security adds an additional layer of security to the switching network. Port security can also configured locally and has no mechanism for controlling port security in a centralized fashion for distributed switches. Configuring dynamic switchport security free ccna workbook. Configuring sticky switchport security free ccna workbook. A secure port cannot be a destination port for switch port analyzer span. Use show portsecurity interface to see the port security details per interface.
Catalyst 4500 series switch cisco ios software configuration guide. I have some questions regarding to port security on my 2690 catalyst. Note when a catalyst 4500 series switch port is configured to support voice as well as port security, the maximum number of allowable mac addresses on this port should be changed to three. Cisco switch port security packet tracer demonstration part 1 demonstrating switch port. Switchport security is not supported along with etherchannel fast or gigabit. Almost all cisco devices use cisco ios to operate and cisco cli to be managed. Do not configure span destination on a secure port. 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. The reason may be that it requires a more granular configuration. Finally, a security checklist for cisco switches summarizes the countermeasures. Cisco switch port security configuration gpon solution. The family supports 40g or 10g uplinks, physical stacking, up to 60w of port.
In this article, we will focus on detailed port security configuration. For our configuration, we will use the below topology consist of one switch, one hub and four pcs. Enable portsecurity on sw1s fa01 interface and configure the interface to sticky the mac address learned. Do not configure dynamic, static, or permanent cam entries on a secure port.
Catalyst 2960 switch software configuration guide ol860301 configuring the switch for local authentication and authorization 832 configuring the switch for secure shell 833 understanding ssh 833 ssh servers, integrated clients, and supported versions 833 limitations 834 configuring ssh 834 configuration guidelines 834 setting up the switch to run ssh 835. Switchport security can only be configured on statically configured access or trunk ports access or trunk. Feb 02, 2011 demonstrating switch port security using packet tracer for the cisco ccna. Double encapsulation can be initiated by an attacker who has access to a switch port belonging to the native vlan of the trunk port. After port security has determined a mac address violation, it can use one of four violation modes. Mar 11, 2016 follow the below commands to configure port security on a cisco switch. Move all unused switch ports to the blackhole vlan. Meraki switches do not require cli for switch configuration or port management. Do not configure port security on a span destination port. For ports f01 on sw1, statically configure the mac address of the pc using port.
With port security, you can associate specific mac addresses with specific interfaces on your switch. Here is a cisco commands cheat sheet that describes the basic commands for configuring, securing and troubleshooting cisco network devices. To configure port security we need to access the command prompt of switch. To enable port security on a specific port you use the switchport port security command in interface configuration mode as shown below sw1 con0 is now available press return to get started. Access the command line for s1 and enable port security on fast ethernet ports 01 and 02.
The default configuration on the switch is to have the management of the switch controlled through vlan 1. Feb 24, 2016 port security is a topic on the ccent exam and its important to know what it is and how to configure it. You can see the violation mode is shutdown and that the last violation was caused by mac address 0e. Catalyst ciscos flagship switching platform, with a large selection of models spanning access, distribution, and core layers. A switch that does not provide port security allows an attacker to attach a system to an unused, enabled port and to perform information gathering or attacks. Huawei port security configuration on huawei ensp in this configuration example, we will configure port security on a huawei switch. Lets now see the basic portsecurity configuration on cisco switches. Port security configuration on cisco switch using packet. 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. However, a best practice for basic switch configuration is to change the management vlan to a vlan other than vlan 1.
Cisco switch port security commands the tech factors. Follow these guidelines when configuring port security. Next, by using the show port security interface fa01 we can see that the switch has learned the mac address of host a. All cisco switch ports or interfaces should be secured before the is is deployed in the data center. To disable port security aging for all secure addresses on a port, use the no switchport portsecurity aging time interface configuration command. Switchport security concepts and configuration cisco press. To view port security configuration and status for a specific interface. Cisco switch port security configuration and best practices. How to configure switch port security cisco certification. How to configure port security sysnettech solutions. One way to boost network security is to use cisco s port security feature to lock down switch ports. The basic cli commands for all of them are the same, which simplifies cisco device management.
When we want to take total control of our switch port that who can access the port and who will not, then we. Mar 29, 2020 this article describes how to configure switch port security on cisco switches. 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. If you disable sticky learning by using the no switchport port security macaddress sticky interface configuration command or the running configuration is removed, the sticky secure mac addresses remain part of the running configuration but are removed from the address table.
Once a switch learns a mac address, it will not accept anything beyond that maximum number. Merakis centralized management platform gives administrators granular visibility into their. As we know, switches learn mac addresses, and so this is going to be dynamic. Port security is easy to configured and it allows you to secure access to a port based upon a mac address basis. We can protect switch by enabling password and console password protection but the main problem come when we think about cisco switches ports which are open for all. Switchport security configuration example to wrap the configuration commands into a single example to ensure clarity, this section will show a basic switchport security example. Keeping track of all of this information in a medium to large organization can. One of the best practices in network security is to try and stop security threats from the entrypoint of a lan network. From privilege exec mode use configure terminal command to enter in global configuration mode. As to your question, how does switch separate the traffic, its via vlans. The implications and reasoning behind this action are explained in the next chapter.
A secure port and static mac address configuration are mutually exclusive. To enable portsecurity youll execute the switchport portsecurity command as previously learned in lab 419. This section lists the guidelines for configuring port security. The cisco meraki ms355 series provides full 10g multigigabit mgig access switching for demanding enterprise and campus environments. Cisco switch port security best cisco ccna ccnp and linux. Optional sets the maximum number of secure mac addresses for the interface. Port security does not support switch port analyzer span destination ports. Luckily, there is a feature on cisco switches called port security that can help you mitigate the threat. Best cisco ccna ccnp and linuxcentos pdf notes new ccna routing and switching 200125 ccna security and ccna voice best ever ccnp route300101 and 642902 and switch and also best rhcerhcsa linux notes for rhel6 and rhel 7 and also ubuntu and pfsense firewall pdf notes.
Refer to configuring source guard in the cisco nxos security configuration guide for more information about this feature. Oct 11, 2007 one way to boost network security is to use cisco s port security feature to lock down switch ports. A secure port cannot belong to an etherchannel portchannel interface. The best advise is to follow this video through, then. I belive the switch port remember the binded mac address as long as port security is enabled. To do this, the interface of the port is configured as an access port with the switchport mode access command. Here is a useful command to check your port security configuration. When you are working as a network engineer or network administrator the main problem you facing is the security of switch. Port security must be configured for all cisco switches to be installed to limits the number of valid mac addresses allowed on a port and all unused ports must be disabled.
Cisco ios software configuration guide, release 12. Securing cisco switches configuring port security icnd1. Btw dont forget, generally you connect the voip phone to the switch port and the pc to the voip phone. Catalyst 2960 switch software configuration guide ol860301 contents preface xliii audience xliii purpose xliii conventions xliv related publications xliv obtaining documentation xlv cisco.
First, we need to enable port security and define which mac addresses are allowed to send frames. This means that the switch can play an important role in network security since its the entrypoint of the network. On a trunk, if you do not configure a vlan for a st atic secure mac address, it is secure in the vlan configured with the switchport trunk native vlan command. With the default port security configuration, to bring all secure ports out of the errordisabled state, enter the errdisable recovery cause psecureviolation global configuration command, or manually reenable the port by entering the shutdown. Switch configuration port security this video will demonstraight how to configure the switch hostname, all service passwords and how to setup and configure port. The implications and reasoning behind this action are explained in. The switch series features a high mgig port density for 802. Port security is either autoconfigured or enabled manually by specifying a mac address.
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