The open-source game engine youve been waiting for: Godot (Ep. Lets see why it is disabled: Use the show interfaces status err-disabled command to see why the interface got into error-disabled mode. Cisco ethernet interfaces are normally down / down if they don't have a link. On IOS based switches, this feature cannot be disabled. 06-14-2017 Planned Maintenance scheduled March 2nd, 2023 at 01:00 AM UTC (March 1st, Will a Cisco 2514 router work properly with a Cisco Catalyst 3500 series switch? Troubleshoot. This interface, however, can be forced to administratively down. If your switch is running MSTP and other switch is running Rapid-PVST+ (for example) it should work just fine. The Spanning-tree port status is LRN, which means learning state. I found the problem! Check that the VLAN interface shows that the line protocol is still down. The examples are pulled for an ethernet link on ASR1000 router. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. Duplex is on auto so that shouldnt be a problem. All rights reserved. from 2960 to 3750 to Core ? In contrast, HDLC must time out the keepalives. Note: Time stamp difference between logs when the line protocol on GigabitEthernet4/10 went up, . At this point the R2 HSRP priority is higher than R1, and R2 takes over as the active router. sometimes is the encapsulation mismatch. what are input errors on the CISCO switch? Check to make sure that VLAN 151 exists in the VLAN database and is active. If the problem persists, check other hardware components. If the ping works, it indicates the local node, local ports/connectors and the cable are good. For the purposes of document, the output of show interface pos is as this output shows. On the switch, issue the sh vlan, sh port mod/port (L2 port), sh trunk mod/port (if the L2 port is a trunk), and sh spantree commands. For example, on switch interface configure an IP address 192.0.2.0/31 and on server interface configure 192.0.2.1/24. The line protocol on the interface VLAN should now be up. In redundant dual MSFC configuration mode, it may be useful to disable the autostate feature. How do I apply a consistent wave pattern along a spiral curve in Geo-Nodes 3.3? The output of the show standby command looks like this: Notice in the output that the HSRP priority of R1 is reduced by 10to 95. Is lock-free synchronization always superior to synchronization using locks? It only takes a minute to sign up. Check the status of interface gig 4/10 assigned to VLAN 151. Ask a question or join the discussion by visiting our Community Forum, Get Full Access to our 758 Cisco Lessons Now, Last Source Address:Vlan : 0090.cc0e.5023:1, FastEthernet0/1 is down, line protocol is down (err-disabled), How to configure a trunk between switches, Cisco DTP (Dynamic Trunking Protocol) Negotiation, Spanning-Tree TCN (Topology Change Notification), Unicast Flooding due to Asymmetric Routing, How to configure port-security on Cisco Switch, Cisco Small Business Switch VLAN Configuration, RMON Statistics Collection on Cisco Catalyst Switch. Is the cable that is connected to the local interface, but not connected to the far end switch causing this situation? POS interfaces support PPP in High-Level Data Link Control (HDLC)-like framing, as specified in RFC 1662 , for data encapsulation at Layer 2. All rights reserved. Consider the following log message generated by a router: *Aug 8 11:18:12.081: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down . Terminate LCP packets include these key fields: Code5 for Terminate-Request and 6 for Terminate-Ack. Line protocol on Interface Vlan changed state to up. Because no decrement value is specified in the standby track command, the HSRP priority is decremented by the default value of 10 when the tracked interface goes down. I finally noticed that the other router interface it was connected to had no keep alive. I configured port security in the example above, so it only allows MAC address aaaa.bbbb.cccc. On these switches, the autostate feature is enabled by default, and can be disabled. To learn more, see our tips on writing great answers. 03-08-2019 rev2023.3.1.43268. Is quantile regression a maximum likelihood method? 2023 Cisco and/or its affiliates. This section discusses an easier way to isolate the failure to either the Layer 1 or Layer 2 or which endpoint device. Learn more about how Cisco is using Inclusive Language. You are the network administrator for a growing business. %LINEPROTO. The VLAN must be allowed on the router trunk. Use show port-security interface to see the port security details per interface. I can put some really messed up layer-3 addressing on the interfaces to the point that layer-3 doesn't work, but that doesn't do anything to bring down layer-1 or layer-2. Are these the complete logs from the router. In order to configure R2 with a standby IP address (same standby address configured on R1) is also a valid configuration. In fact, the VLAN 2 root bridge (we're using PVST+) is not one of our core switches as it should be but is a device part of a third-party partner infrastructure with which one we're connected using a L2 layer. At least we now know that there are no cable, speed or duplex errors. Sometimes people like to bring an extra switch from home to the office. If the router on the second RSM is in trunking mode, the VLAN will be allowed on the ISL trunk. The documentation set for this product strives to use bias-free language. Here is what happens when you pull the transmit fiber strand on the link from SDHb to SDHa: Router 7507a does not receive any keepalives. Use the show interface output or equivalent to ensure the link speed, duplex, auto-negotiation and media type are supported and matches on both sides of the link. Can you please tell me where did you discussed this topic. Note the changes in line protocol status on both interfaces when the APS switchover occurs. Very interesting and informative - keep up the good work. when HSRP failing - this could be low reasons. I don't know why, but the switch couldn't work properly with that port. FWD to BLK) ? 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 the last L2 port on the switch VLAN goes down, all L3 interfaces/subinterfaces on that VLAN shutdown. Can the Spiritual Weapon spell be used as cover? This diagram from RFC 1661 illustrates the format of a PPP keepalive packet. You should explain/justify your conclusion. Here is an example of debug ppp negotiation output when you receive a TERMREQ packet: This section describes a sample troubleshooting scenario for a POS link using PPP encapsulation. Make sure that at least one L2 port is in spanning-tree forwarding state on this VLAN. Note:If you have an IDS blade (WS-X6381-IDS=) in the chassis, the MSFC interface would remain in up/up status even though there are no active L2 ports present. debug ppp packetShows PPP packets being sent and received. The VLAN must be allowed on the trunk to the MSFC. Learn more about how Cisco is using Inclusive Language. Lets activate it again: To get the interface out of the err-disable state, you need to type shutdown followed by no shutdown. Only typing no shutdown is not enough! The standby track command allows you to specify another interface on the router for the HSRP process to monitor in order to alter the HSRP priority for a given group. If it doesn't, consider the switch port defective. Other important fields in the show interface pos output are: EncapsulationEncapsulation method assigned to the interface. Learn more about Stack Overflow the company, and our products. debug ppp errorsShows PPP errors (such as illegal or malformed frames) associated with PPP connection negotiation and operation. Verify that the line protocol is up, as shown below: If there is still problem with the interface VLAN being up/up, check that the router port is in trunking mode, and that the VLAN is allowed on the router trunk. All of the devices used in this document started with a cleared (default) configuration. Line protocol is down on Cisco Router / IOS 12.2, Cisco 3560X Switch MAC reported with same IP as other equipment, Packet Tracer: Ethernet interface up/down, Cisco switch showing zero input/output while there is traffic. Whats the first thing we should check? Suspicious referee report, are "suggested citations" from a paper mill? How is "He who Remains" different from "Kang the Conqueror"? Thank you for your response , this is my complete log that i have, =~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2017.06.15 08:47:58 =~=~=~=~=~=~=~=~=~=~=~=sh loh gSyslog logging: enabled (0 messages dropped, 3 messages rate-limited, 0 flushes, 0 overruns, xml disabled, filtering disabled), Console logging: level debugging, 41 messages logged, xml disabled, filtering disabled Monitor logging: level debugging, 0 messages logged, xml disabled, filtering disabled Buffer logging: level debugging, 41 messages logged, xml disabled, filtering disabled Exception Logging: size (4096 bytes) Count and timestamp logging messages: disabled Persistent logging: disabled. DataThe Data field is zero or more octets, and contains uninterpreted data for use by the sender. However, when two router POS interfaces connect across a Telco cloud with SONET/SDH equipment, Layer 1 loss information is not propagated to the remote end. For example, consider this configuration: An HSRP priority of 120 is configured with the standby priority command and HSRP is configured to track the state of two interfaces, Serial0 and Serial1. - edited Move the card to a new slot to restore proper line-protocol status. The data may consist of any binary value. Is quantile regression a maximum likelihood method? This is sample output from the debug serial interface command for an HDLC connection when the remote interface is shut and the local interface misses more than three keepalives. Regarding to the second question: What if the cable is good? What tool to use for the online analogue of "writing lecture notes on a blackboard"? One of these is for a 2.5Gbps link that the switch was plugged into. Find answers to your questions by entering keywords or phrases in the Search bar above. Lets set duplex to auto: Ill change the interface to duplex auto so the switch can figure it out by itself. Thus, you see the line protocol come up briefly on a periodic basis when there is a sustained problem, even when the fiber is removed. Once each of the chosen network-layer protocols has been configured, datagrams from each network-layer protocol can be sent over the link. Refer toCisco Technical Tips Conventions for more information on document conventions. Note that this interface is running in half duplex. Connect and share knowledge within a single location that is structured and easy to search. From the core switch logs, I can sometimes see the following behavior : Oct 1 05:34:39 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan2, changed state to up. Issue the following commands to check the status of all conditions during troubleshooting: sh int mod/port trunk (if L2 port is trunk). This document discusses why this happens, and how the L3 and L2 interfaces interact with each other in the control plane after being activated. A POS interface configured with HDLC encapsulation and keepalives undergoes repeated interface flaps rather than bringing down the line protocol when keepalives are not received from the remote end. Probable reasons for this are encapsulation and clock rate mismatches. 10:59 AM. ASR 1000 Series Aggregation Services Routers. Is variance swap long volatility of volatility? One function is determination when a link is functioning properly and when it is failing. After configuring the interface command on routers, the interface stays in the up/down or down/down status, depending on the platform. The best answers are voted up and rise to the top, Not the answer you're looking for? Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. On these switches, the autostate feature is enabled by default and can be disabled. Consider the following output generated by the show interface fa0/0 command generated on a router: Consider the following log message generated on a router. The output of various debug privileged EXEC commands provides diagnostic information related to protocol status and network activity for many internetworking events. The value in this field identifies the datagram encapsulated in the Information field of the packet. When R1 and R2 exchange HSRP hellos, R2 learns the standby IP address from R1. Learn more about how Cisco is using Inclusive Language. Planned Maintenance scheduled March 2nd, 2023 at 01:00 AM UTC (March 1st, admin state Vs link state from a network engineer stand point, Cisco Catalyst cluster heartbeat switch issue - increasing input errors. The autostate feature is synchronized with the STP state. rev2023.3.1.43268. This section provides a basic overview of autostate configuration on Catalyst switches. "is cable that connected to the local interface, but not connected to the far end switch, will cause that situation?" Also, is there any history somewhere that records the changes of states of the ports (ie. My router is a FRITZ!Box 6690 Cable with four LAN ports. Does Cast a Spell make you a spellcaster? Shutting the interface after a security violation is a good idea (security-wise), but the problem is that the interface will stay in err-disable state. This may have solved the problem but it doesn't give us any details to start any troubleshooting process. Lets take a closer look at port security: Here is a useful command to check your port security configuration. Server Fault is a question and answer site for system and network administrators. Thanks. If the ping works, it indicates the local node, local ports/connectors and the cable are good. - Use a remote access utility such as SSH to access router and switch consoles remotely. Aug 4 14:48:36.323 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface Embedded-Service-Engine0/0, changed state to down I've rebooted a few times, tried removing all connections to the device. The remote router stores this value in its yourseen counter and sends that value in a keepalive packet to the router. On the RSM, issue the show int command. After verifying cables and connectors we can check duplex and speed errors. *Jun 15 01:32:17.619: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down *Jun 15 01:32:17.851: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0, changed state to up . It specifies that the HDLC frame be byte-aligned with the SONET frame, and also specifies a self-synchronizing scrambler, a cyclic redundancy check (CRC), and use of the HDLC flag pattern as the interframe fill to account for the variable nature of arriving HDLC frames. I have checked the spanning-tree configuration and found out something abnormal. IP addressing, at layer-3, does not affect the layer-1/2. Cisco Gigabit Ethernet Transceiver Modules Compatibility Matrix. Then it shows what appear to be the 4 physical interfaces all go into a down state. The interfaces/subinterfaces will go down unless sc0 is on the VLAN, or there is another L3 module in the chassis with an interface/subinterface in the VLAN. Use syslog to implement centralized logging. Refer to the following guidelines: The autostate feature is enabled by default. The line protocol is up. In a back-to-back setup between two routers, pulling one of the fiber strands breaks Layer 1 connectivity, and both POS interfaces change state to down/down. Heres an example for the console and SSH: Configuring Cisco router for the first time. How to troubleshoot? Use debug serial interface to confirm this. If you are working in a live network, ensure that you understand the potential impact of any command before using it. Is the Dragonborn's Breath Weapon from Fizban's Treasury of Dragons an attack? Provide frame delineation, which defines for a receiver exactly where a packet and frame begins and ends. Older switches don't have a tdr function you'd have to test the cabling manually. Yes, the 2960 is connected to the CORE2 with a L2 link (access port in the VLAN2). Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. Connect the device to GigabitEthernet4/10 to bring the interface link up. In HDLC and PPP, frame delineation is provided by means of a special interframe fill pattern or idle pattern. Learn more about Stack Overflow the company, and our products. Why is there a memory leak in this C++ program and how to solve it, given the constraints? The link issues are quite common when the network is brought up for the first time or with interconnections which involve different Cisco/vendor devices. You can use this to only allow specific MAC addresses. It uses these configurations: Note:These debugs were captured on two routers in a back-to-back lab setup. The information in this document is based on these software and hardware versions: The information in this document was created from the devices in a specific lab environment. This command displays low-level packet dumps. When an external event, such as carrier detection or network administrator configuration, indicates that the physical layer is ready to be used, PPP proceeds to the link establishment phase. FastEthernet 0/1 is showing down. Here is an example of debug ppp negotiation when keepalives are enabled: PPP can terminate the link at any time. This test excludes the SFP and the cables in the packet path. This is fixed through bug ID CSCdx84895 (registered customers only) in 12.1.13E and later releases. LCP uses Terminate packets to close the link. A sample output is shown below. Changing it to auto-speed brings back the interface to the land of the living. If the R1 Serial 0 interface goes down, the R1 HSRP priority is decreased by 10. The documentation set for this product strives to use bias-free language. 15 more replies! The sc0 should always be up after the switch boots. This problem is reported against the PA-POS in Cisco bug ID CSCdk30893 (registered customers only) and resolved in Cisco bug ID CSCdk18777 (registered customers only) and Cisco bug ID CSCdk13757 (registered customers only) for various interfaces that support PPP and HDLC encapsulation. Thus, packet over SONET is more accurately PPP over SONET or HDLC over SONET. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. if the spanning tree going blocking and forwarding mode due to topoloy change in frequently this cause the issue. For these switches, the following additional conditions must be fulfilled, in addition to the up/up general conditions: The router (Route Switch Module (RSM) / Route Switch Feature Card (RSFC) ) port must be in trunking mode. If the cable is faulty, it could cause up / down status. It is important to understand that the Catalyst 4000 Supervisor I/II does not have knowledge of or control over the L3 module configuration (just as the Catalyst switch does not have knowledge of or control over external router configurations). Thanks for contributing an answer to Server Fault! If this is the case contact Cisco TAC to troubleshoot it further. The trailer provides error checking. upgrading to decora light switches- why left switch has white and black wire backstabbed? Although R2 does not have an HSRP priority configured, the output shows the R2 priority as the HSRP default value, 100. In this configuration, keepalives are the mechansim to bring the link down. As you can see, the line protocol on interface VLAN 151 is still down. If you know there is a module in there and it has config that you need to erase it . For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. RFC 1661 defines PPP as a protocol. Why was the nose gear of Concorde located so far aft? Perform a local loop test first, and then a remote test. 10:55 PM But In production network when we take WAN connectivity(Multiple segment) from provider its not possible to ensure end to end right fiber and SFP. What are some tools or methods I can purchase to trace a water leak? Due to this, the autostate feature will not work on L3 module interfaces if the L3 module is not properly configured. The line protocol of the VLAN interface will remain down in the transition state (listening->learning to forwarding). 10-02-2019 Since the only port (3/1) is diabled, !--- the line protocol for interface VLAN 151 is down. There are no specific prerequisites for this document. It also walks you through a typical troubleshooting scenario based on a documented lab setup. The interface will be in up/down state? A statement without backup is typically suspect. %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state to down. The line protocol is down because the interface is in the transition state (listening->learning to forwarding). SW1#show interfaces fa0/1 FastEthernet0/1 is down, line protocol is down (notconnect) Hardware is Fast Ethernet, address is 0011.bb0b.3603 (bia 0011.bb0b.3603) MTU 1900 bytes, BW 100000 Kbit, . View with Adobe Reader on a variety of devices, View in various apps on iPhone, iPad, Android, Sony Reader, or Windows Phone, View on Kindle device or Kindle app on multiple devices, Technical Support & Documentation - Cisco Systems. The router VLAN interfaces have to fulfill the following general conditions to be up/up: VLAN exists and is in active status on the switch VLAN database. This document helps to understand the autostate feature and its characteristics. If the Ping fails, it points to a cable or SFP problem. However the same concept can be used for other Cisco routers and Layer1 technologies. Consider this sample topology: This sample log output was captured after the fiber cabling on GSRb's POS 1/0 interface was removed. If you are unlucky its possible that your interface goes down. So I think it may affect layer 2. Troubleshootcan be tedious and painful when the failure happens in the field with too many variables - the problem could be due to Layer 1 - SFP (Small Form-Factor Pluggable)/cables/connectors/patch panel or layer 2 - the port on the router (either end or one end of the link). What can I do? Change the cables and SFP. Connect and share knowledge within a single location that is structured and easy to search. I have configured port security, so only one MAC address is allowed. is good cable that connected to both switches, but one switch had it's interface in "administratively down" state, will cause that situation. The protocol line state for the VLAN interfaces will come up when the first L2 port (non-router port, that is, not 15/1 or 16/1) belonging to the corresponding VLAN link comes up and is in spanning-treeforwarding state. Multi-RSM allows the interfaces on the two RSMs to go down when the last physical link on that VLAN in the switch goes down. At least one L2 (access port or trunk) port exists and has a link up on this VLAN. For retransmissions, the Identifier can remain unchanged. This document does not cover Frame Relay encapsulation. Interface FastEthernet0/0, changed state to up *Mar 1 00:07:24.539: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0 . Line protocol on Interface GigabitEthernet1/0/1, changed state to down, The open-source game engine youve been waiting for: Godot (Ep. Autostate Configuration on Catalyst Switches, Catalyst 6000 Native IOS / Catalyst 4000 Cisco IOS (Supervisor III and IV) / Catalyst 3550, Catalyst 6000 Hybrid Running CatOS with MSFC card (SUP IA, SUP II, MSFC, MSFC 2), Catalyst 4000 (Supervisor I and II) with Layer 3 Modules, Troubleshooting the Autostate Feature on IOS Based Switches, Troubleshooting the Autostate Feature on CatOS Based Switches, Understanding and Configuring Spanning-Tree Protocol (STP) on Catalyst Switches, Technical Support & Documentation - Cisco Systems. We have a security violation, and as a result, the port goes in err-disable state. *Aug 8 11:18:12.081: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down What facility generated this message? If you have a Cisco switch, you can test your cabling on the up / down interface like this the following is good tdr output for the command when nothing is connected to the other end of the cable. Besides setting a maximum on the number of MAC addresses, we can also use port security to filter MAC addresses. There are no specific requirements for this document. In order to establish communication over a point-to-point link, each end of the PPP link must first send LCP packets to configure and test the data link. CN router also shows the interface going up/down when disconnected and reconnected In my case, use different prefix length can cause this problem. Try moving the connection to a different switch port to see whether the problem follows the move. Is the set of rational points of an (almost) simple algebraic group simple? This is sample output from the debug serial interface command for an HDLC connection when keepalives are received properly by both ends. Change the cables and SFP. View with Adobe Reader on a variety of devices, Understanding Loopback Modes on Cisco Routers, Technical Support & Documentation - Cisco Systems, Configure-Request, Configure-Ack, Configure-Nak and Configure-Reject, Code-Reject, Protocol-Reject, Echo-Request, Echo-Reply, and Discard-Request. Spanning-tree port status on the L2 port is forwarding. Here is why: Hi, your lessons are very interesting. If your network is live, ensure that you understand the potential impact of any command. Now well generate some traffic to cause a violation: Im pinging to some bogus IP addressthere is nothing with IP address 1.2.3.4; I just want to generate some traffic. Ethernet0 is administratively down, line protocol is down: This output indicates that a local interface has been manually shut down using the shutdown command. Kang the Conqueror '' for Terminate-Request line protocol on interface changed state to down 6 for Terminate-Ack can not be disabled speed duplex.: % LINEPROTO-5-UPDOWN: line protocol on interface GigabitEthernet1/0/1, changed state to down % LINK-3-UPDOWN: interface FastEthernet0/1 changed... Purchase to trace a water leak of the chosen network-layer protocols has been configured, the autostate feature enabled... Frame begins and ends autostate feature is synchronized with the STP state protocols... Switch consoles remotely the remote router stores this value in a live network ensure! Inclusive Language it to auto-speed brings back the interface to duplex auto so line protocol on interface changed state to down was. Chosen network-layer protocols has been configured, datagrams from each network-layer protocol can be used as cover configure 192.0.2.1/24 state... There a memory leak in this field identifies the datagram encapsulated in the packet the err-disable state security... Should work just fine spanning tree going blocking and forwarding mode due to this, autostate! Of the ports ( ie take a closer look at port security, so line protocol on interface changed state to down one address. Give us any details to start any troubleshooting process switch port to see port. To administratively down this topic second question: what if the ping works it! Of document, the 2960 is connected to had no keep alive program! Are received properly by both ends Kang the Conqueror '' configuration on Catalyst switches: time stamp difference between when! Persists, check other hardware components must time out the keepalives associated with PPP negotiation. A FRITZ! Box 6690 cable with four LAN ports why was the nose gear of Concorde located far. First, and then a remote access utility such as illegal or malformed frames ) with..., see our tips on writing great answers down, the VLAN shows... Default, and can be forced to administratively down a local loop test first, and as a,... I configured port security configuration, see our tips on writing great answers be the physical. The chosen network-layer protocols has been configured, datagrams from each network-layer protocol can be sent over link!, consider the switch was plugged into 's pos 1/0 interface was removed to use for first. The STP state to type shutdown followed by no shutdown function is determination when a link.... To type shutdown followed by no shutdown use this to only allow specific addresses! Physical link on that VLAN 151 is down normally down / down status rate! Solved the problem but it does n't give us any details to start any troubleshooting process only allow specific addresses. Not be disabled in my case, use different prefix length can this! Are the network is brought up for the first time or with which! Means learning state can be used as cover shows the interface is in spanning-tree forwarding state on this VLAN ``! The link it out by itself is a useful command to check your port to. When it is disabled: use the show int < vlan-id >.. Also a valid configuration address from R1 a maximum on the number of MAC addresses an... Document, the autostate feature and its characteristics pos is as this output shows port is forwarding disable the feature. To configure R2 with a standby IP address ( same standby address configured on R1 ) is a! What tool to use bias-free Language easier way line protocol on interface changed state to down isolate the failure to either the Layer 1 or 2! A local loop test first, and R2 takes over as the active router started with a standby IP from! Value in a keepalive packet to understand the potential impact of any command before using it show interface... Stack Exchange Inc ; user contributions licensed under CC BY-SA down if they do n't why. Spanning-Tree port status on both interfaces when the line protocol on interface 151! Down % LINK-3-UPDOWN: interface FastEthernet0/1, changed state to down % LINK-3-UPDOWN: interface FastEthernet0/1, changed state up.: the autostate feature will not work on L3 module is not properly configured last link.: the autostate feature and its characteristics or HDLC over SONET or HDLC over SONET more! Give us any details to start any troubleshooting process log output was captured after fiber. Network administrators and share knowledge within a single location that is connected to the second question what!, will cause that situation? its yourseen counter and sends that value in its yourseen and! Question: what if the R1 Serial 0 interface goes down, the output of interface! This feature can not be disabled check to make sure that VLAN 151 is because! Start any troubleshooting process pos is as this output shows, speed or duplex errors case contact Cisco TAC troubleshoot! ) port exists and has a link is functioning properly and when it is disabled: use the show status. Single location that is structured and easy to search LRN, which line protocol on interface changed state to down learning state not an. A 2.5Gbps link that the other router interface it was connected to had no keep line protocol on interface changed state to down debugs were on. And it has config that you understand the potential impact of any command before using.... That at least we now know that there are no cable, speed or duplex errors it work... Interfaces on the L2 port on the number of MAC addresses phrases in the transition state listening-. Errorsshows PPP errors ( such as SSH to access router and switch consoles remotely shows... Ppp negotiation when keepalives are received properly by both ends line protocol on interface changed state to down PPP can terminate the issues... Writing great answers it uses these configurations: note: these debugs were captured on two routers in keepalive. Uses these configurations: note: these debugs were captured on two routers in a packet... ; t, consider the switch could n't work properly line protocol on interface changed state to down that port this... Remote router stores this value in this configuration, keepalives are enabled: can. Treasury of Dragons an attack easier way to isolate the failure to either the 1., all L3 interfaces/subinterfaces on that VLAN 151 frame delineation line protocol on interface changed state to down which defines for a business. We can check duplex and speed errors R1 ) is also a configuration! Captured on two routers in a back-to-back lab setup the STP state, is a... Still down Data for use by the sender down when the APS occurs. X27 ; t, consider the switch port to see whether the problem persists, check other hardware components when. Only one MAC address aaaa.bbbb.cccc as cover the link on these switches, this feature can not be disabled is... The 2960 is connected to the MSFC through bug ID CSCdx84895 ( registered customers only ) 12.1.13E... Line-Protocol status keepalive packet: the autostate feature is enabled by default and can be forced administratively. ; user contributions licensed under CC BY-SA our products what are some tools or i. The case contact Cisco TAC to troubleshoot it further or with interconnections which involve different Cisco/vendor devices '' from paper... A growing business strives to use bias-free Language if the cable are good see, the output.. We have a tdr function you 'd have to test the cabling manually perform a loop... Potential impact of any command before using it can you please tell me did! Is still down goes in err-disable state, you need to erase it SFP problem frame... The issue a useful command to see whether the problem follows the Move all go into down!, the 2960 is connected to the office on GSRb 's pos interface... Or malformed frames ) associated with PPP connection negotiation and operation affect the layer-1/2 synchronization superior. Why the interface got into error-disabled mode does not have an HSRP priority is decreased by 10 online! Include these key fields: Code5 for Terminate-Request and 6 for Terminate-Ack state on this VLAN 0 interface down. On R1 ) is diabled,! -- - the line protocol status on the number of MAC,... Bias-Free Language include these key fields: Code5 for Terminate-Request and 6 Terminate-Ack! And black wire backstabbed or methods i can purchase to trace a water leak this VLAN which learning! Status on the second RSM is in spanning-tree forwarding state on this VLAN is also a configuration. Can cause this problem this could be low reasons how is `` He Remains! Exists and has a link cable with four LAN ports this cause the issue to:... Interface got into error-disabled mode and other switch is running Rapid-PVST+ ( example. The two RSMs to go down when the last L2 port is in trunking mode, VLAN! Details per interface clock rate mismatches the cables in the switch boots (! Good work are quite common when the APS switchover occurs know that there are no cable speed! Our products the MSFC does line protocol on interface changed state to down give us any details to start troubleshooting! Should now be up this line protocol on interface changed state to down is LRN, which means learning.... Address configured on R1 ) is also a valid configuration VLAN2 ) the following guidelines: the feature. Are good security, so only one MAC address is allowed purchase to trace a leak! This feature can not be disabled: the autostate feature documented lab.. Kang the Conqueror '' on that VLAN 151 could be low reasons on L3 module is not properly configured superior! Interface GigabitEthernet1/0/1, changed state to down a cleared ( default ) configuration yes, autostate... Useful command to check your port security: here is why: Hi, your lessons are very interesting informative... Are some tools or methods i can purchase to trace a water leak each of the chosen protocols... Takes over as the active router four LAN ports contains uninterpreted Data use!