These LCP packets include these key fields: Code9 for Echo-Request and 10 for Echo-Reply. This document does not cover Frame Relay encapsulation. The output of both routers indicates that the routers track the state of the Serial interface. Here is a conceptual diagram of the switches involved into this situation : CORE SWITCH 1 [HSRP active] (3750X) <------ trunk link with many vlans ------>CORE SWITCH 2 [HSRP standby] (3750X) <--- mode access vlan 2 ---> Access switch (2960X). Another card inserted in the same slot experiences this problem. Asking for help, clarification, or responding to other answers. LCP Echo-Request and Echo-Reply packets provide a Layer 2 loopback mechanism for both directions of the link. It uses these configurations: Note:These debugs were captured on two routers in a back-to-back lab setup. This should ring a couple of alarm bells (at least it means we are onto something). Whats the first thing we should check? Is variance swap long volatility of volatility? Use a spare port on the same router and connect the port to be tested to it with the same cable and connectors/SFP. If port 3/1 is trunking, issue the sh trunk command to check if VLAN 151 is allowed. No, it is point-to-point at layer-3. *Aug 8 11:18:12.081: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down What facility generated this message? To use this feature, autostate must be enabled. Refer to bug ID CSCdu05914 (registered customers only) for more information. - Consolidate network resources down to one or two switches. Issue the following commands to check the status of all conditions during troubleshooting: sh int mod/port trunk (if L2 port is trunk). 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. It also walks you through a typical troubleshooting scenario based on a documented lab setup. Yes, the 2960 is connected to the CORE2 with a L2 link (access port in the VLAN2). Switch interfaces are layer-2 interfaces, but if you can address it, then you have enabled layer-3 and it is a router interface. Can you post the configuration and spanning-tree config ? Alternatively, you can post and accept your own answer. whick menas that keepalives will not be receiver on the far end. Now, if the R1 serial 0 interface comes back up, the R1 priority is 105, again. The interface will be in up/down state? 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. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Consider this sample topology: This sample log output was captured after the fiber cabling on GSRb's POS 1/0 interface was removed. 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. debug ppp errorsShows PPP errors (such as illegal or malformed frames) associated with PPP connection negotiation and operation. 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. I have configured port security, so only one MAC address is allowed. The frame format for PPP in HDLC-like framing is shown in this figure. If the line protocol of the specified interface goes down, the HSRP priority is reduced. As a result, our Cisco switch will learn the MAC address of H1 and H2 on its FastEthernet 0/1 interface. I have checked the spanning-tree configuration and found out something abnormal. "is cable that connected to the local interface, but not connected to the far end switch, will cause that situation?" - Hire additional resources to help monitor and manage your network infrastructure. When a lower priority active router receives a Coup message or a Hello message from an active, higher priority router, the router changes to the Speak state and sends a resign message. The autostate feature notifies a switch or routing module VLAN interface (Layer 3 (L3) interface) to transition to up/up status when at least one Layer 2 (L2) port becomes active in that VLAN. The trailer provides error checking. Thanks. Due to this, the autostate feature will not work on L3 module interfaces if the L3 module is not properly configured. *Mar 1 01:54:39.699: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel0, changed state to up. When the difference in the values in the myseq and mineseen fields exceeds three, the line goes down and the interface is reset. Can I use this tire + rim combination : CONTINENTAL GRAND PRIX 5000 (28mm) + GT540 (24mm). I'm using a Cisco Catalyst 2960-X Series. This behavior is different from the default behavior on the Catalyst 6000 hybrid mode. In the question, the interface is layer-1, and the line protocol is layer-2. In the question, the interface is layer-1, and the line protocol is layer-2. The fault is likely at the remote end or an interoperability issue between the two devices. Note: Time stamp difference between logs when the line protocol on GigabitEthernet4/10 went up, . Help me understand the context behind the "It's okay to be white" question in a recent Rasmussen Poll, and what if anything might these results show? From the core switch logs, I can sometimes see the following behavior : It happens about 4-5 times a day without any visible impact on our production. This sample output captures the LCP link configuration stage on a POS interface: Note:A POS interface configured with PPP encapsulation continually tries to establish a PPP session. On these switches, the autostate feature is enabled by default and can be disabled. This allows traffic to flow between the two RSMs on that VLAN without disabling the autostate feature. 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. When the last L2 port on the switch VLAN goes down, all L3 interfaces/subinterfaces on that VLAN shutdown. Older switches don't have a tdr function you'd have to test the cabling manually. The value in this field identifies the datagram encapsulated in the Information field of the packet. On some CatOS platforms, this feature can be disabled in order to allow redundancy in special scenarios. Line Protocol Is Down With PPP RFC 1661 defines PPP as a protocol. Very interesting and informative - keep up the good work. Embedded-Service-Engine0/0, changed state to down, Customers Also Viewed These Support Documents. Would the reflected sun's radiation melt ice in LEO? POS interfaces support multiple encapsulations - HDLC, PPP and Frame Relay. Glad to hear it was useful to you. Thus, clocking is set to internal on one side and to default to line on the other end. A sample output is shown below. (Refer to the APS Technology Support Page for more information.). Use the switchport port-security mac-address command to define the MAC address that you want to allow. This is the symptom of a VLAN interface being in up/down status. Learn more about how Cisco is using Inclusive Language. The Data field is zero or more octets, and contains uninterpreted data for use by the sender. Click the card to flip Definition 1 / 4 The correct behavior is for the MSFC interface to go down if no L2 port in STP forwarding state is present. If we want, we can change this behavior with port security. *Jan 2 00:00:04.247: %IOS_LICENSE_IMAGE_APPLICATION-6-LICENSE_LEVEL: Module name = c2900 Next reboot level = ipbasek9 and License = ipbasek9*Jan 2 00:00:04.451: %IOS_LICENSE_IMAGE_APPLICATION-6-LICENSE_LEVEL: Module name = c2900 Next reboot level = securityk9 and License = securityk9*Jun 15 01:31:55.639: c3600_scp_set_dstaddr2_idb(184)add = 80 name is Embedded-Service-Engine0/0*Jun 15 01:32:09.175: %CTS-6-ENV_DATA_START_STATE: Environment Data Download in start state*Jun 15 01:32:12.043: %PA-3-PA_INIT_FAILED: Performance Agent failed to initialize (Missing Data License)*Jun 15 01:32:12.067: %VPN_HW-6-INFO_LOC: Crypto engine: onboard 0 State changed to: Initialized *Jun 15 01:32:12.071: %VPN_HW-6-INFO_LOC: Crypto engine: onboard 0 State changed to: Enabled *Jun 15 01:32:16.803: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to up*Jun 15 01:32:16.803: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to up*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*Jun 15 01:32:17.851: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up*Jun 15 01:32:18.963: %SYS-6-CLOCKUPDATE: System clock has been updated from 01:32:18 UTC Thu Jun 15 2017 to 08:32:18 WIB Thu Jun 15 2017, configured from console by console. I ran the command keep alive on that interface and the state changed to up/up.. Did any answer help you? If the problem persists, check other hardware components. what are input errors on the CISCO switch? Line protocol on Interface Vlan changed state to up. If you are unlucky its possible that your interface goes down. Does anything else happen? The documentation set for this product strives to use bias-free language. You should explain/justify your conclusion. Heres an example for the console and SSH: Configuring Cisco router for the first time. R1# 1w0d: %LINK-3-UPDOWN: Interface Serial0, changed state to down 1w0d: %LINEPROTO-5-UPDOWN: Line protocol on Interface . Click here for a complete list of PPP protocol field values . The sc0 should always be up after the switch boots. The Telecordia GR-253 specification, which defines SONET, discusses HDLC-over-SONET Mapping (see Issue 3, Section 3.4.2.3, pp.3-59.) What tool to use for the online analogue of "writing lecture notes on a blackboard"? If an interface is up/down because of APS deselection, PPP tries resetting the interface and continuously transmits PPP negotiation packets. %LINEPROTO. Its also possible to use usernames/passwords instead: What main items check when troubleshooting fiber based interface. In my case, use different prefix length can cause this problem. Keep in mind that a Gigabit interface doesnt support half-duplex. Is the set of rational points of an (almost) simple algebraic group simple? 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. Lets check if all interfaces are up: This is what we are looking for. 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. All rights reserved. If your network is live, ensure that you understand the potential impact of any command. Use these resources to familiarize yourself with the community: The display of Helpful votes has changed click to read more! By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Learn more about Stack Overflow the company, and our products. For the purposes of document, the output of show interface pos is as this output shows. There is one exception for the VLAN assigned to the management interface (sc0) on the switch. When a higher priority router preempts a lower priority router, the router sends a Coup message. Possible triggers include loss of carrier, authentication failure, link quality failure, the expiration of idle-period timer, or the administrative closing of the link. Keepalives are disabled automatically on most POS router hardware. Learn more about how Cisco is using Inclusive Language. This output illustrates the packet exchange captured with debug ppp packet while a link is being established. 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, . I miss the valuable information because at that time i have panic and directly t restart my router, btw thanks for your advice. if the cable is good, both sides will be down. Note: FastEthernet interfaces by-definition can only test two of the four pairs. Thus, packet over SONET is more accurately PPP over SONET or HDLC over SONET. This also prevents other problems, such as routing black holes, from occurring. 2023 Cisco and/or its affiliates. However the interface exists even if the module isn't present. Use syslog to implement centralized logging. The protocol line state for the management interface VLAN on the MSFC will always be up. In any case, the layer-3 addressing doesn't do anything to the layer-1 and layer-2 on the interface. Lets take a closer look at port security: Here is a useful command to check your port security configuration. On reception, the Identifier field of the Terminate-Request is copied into the Identifier field of the Terminate-Ack packet. If it does, check the equipment on the other end. 542), How Intuit democratizes AI development across teams through reusability, We've added a "Necessary cookies only" option to the cookie consent popup. Spanning-tree port status on the L2 port is forwarding. The line protocol of the VLAN interface will remain down in the transition state (listening->learning to forwarding). However, speed has been set to 10 Mbit while this interface is a FastEthernet (100Mbit) link. 15 more replies! PPP is not aware of APS. Configure the interface in local loopback. Alternately, when performing this test, execute the show controller pos command, which displays SONET alarms. If they are not, a possible timing problem exists on the interface card or in the network. FWD to BLK) ? Which of the following is a standard for sending log messages to a central logging server? Making statements based on opinion; back them up with references or personal experience. The documentation set for this product strives to use bias-free language. ASR 1000 Series Aggregation Services Routers. In order to keep the interface VLAN up/up without having a dedicated L2 port assigned to the VLAN, the autostate feature can be disabled. In redundant dual MSFC configuration mode, it may be useful to disable the autostate feature. HDLC uses keepalives and reports the values of three counters in the debug output: myseqIncreases by one each time the router sends a keepalive packet to the remote router. The best answers are voted up and rise to the top, Not the answer you're looking for? This interface, however, can be forced to administratively down. 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 . The autostate feature is synchronized with the STP state, and this behavior cannot be modified unless autostate is enabled. As R2 was configured for standby preempt at the time that the R2 priority became higher, R2 becomes the active router and R1 becomes the standby. Lets check it out: We can look at the port security configuration and we see that only 1 MAC address is allowed. If your switch is running MSTP and other switch is running Rapid-PVST+ (for example) it should work just fine. Thanks for contributing an answer to Server Fault! I don't know why, but the switch couldn't work properly with that port. Note these caveats when you troubleshoot line protocol problems with POS interfaces: A PA-POS interface might reset continuously after the encapsulation is changed from PPP to HDLC. You need to investigate why this line protocol is not up. *Jun 15 01:32:19.759: %SYS-5-CONFIG_I: Configured from memory by console*Jun 15 01:32:20.179: %LINEPROTO-5-UPDOWN: Line protocol on Interface NVI0, changed state to up*Jun 15 01:32:20.723: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan613, changed state to down*Jun 15 01:32:21.115: %LINK-5-CHANGED: Interface Embedded-Service-Engine0/0, changed state to administratively down*Jun 15 01:32:22.147: %LINEPROTO-5-UPDOWN: Line protocol on Interface Embedded-Service-Engine0/0, changed state to down*Jun 15 01:32:22.919: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/0, changed state to down*Jun 15 01:32:22.919: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to down*Jun 15 01:32:22.919: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/2, changed state to down*Jun 15 01:32:22.919: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/3, changed state to down*Jun 15 01:32:23.591: %SYS-5-RESTART: System restarted --Cisco IOS Software, C2900 Software (C2900-UNIVERSALK9-M), Version 15.4(3)M3, RELEASE SOFTWARE (fc2)Technical Support: http://www.cisco.com/techsupportCopyright (c) 1986-2015 by Cisco Systems, Inc.Compiled Fri 05-Jun-15 13:24 by prod_rel_team*Jun 15 01:32:23.631: %SNMP-5-COLDSTART: SNMP agent on host Router-Mitra-2 is undergoing a cold start*Jun 15 01:32:24.555: %CRYPTO-6-ISAKMP_ON_OFF: ISAKMP is OFF*Jun 15 01:32:24.555: %CRYPTO-6-GDOI_ON_OFF: GDOI is OFF*Jun 15 01:32:24.555: %CRYPTO-6-ISAKMP_ON_OFF: ISAKMP is OFF*Jun 15 01:32:24.555: %CRYPTO-6-GDOI_ON_OFF: GDOI is OFF*Jun 15 01:32:24.555: %CRYPTO-6-ISAKMP_ON_OFF: ISAKMP is ON*Jun 15 01:32:25.287: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up*Jun 15 01:32:26.251: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/1, changed state to up*Jun 15 01:32:26.271: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to up*Jun 15 01:32:27.251: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up*Jun 15 01:32:27.271: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/0, changed state to up*Jun 15 01:32:55.271: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan613, changed state to up*Jun 15 01:33:02.227: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 10.1.191.51] [localport: 23] at 08:33:02 WIB Thu Jun 15 2017*Jun 15 01:34:26.295: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 10.1.10.2] [localport: 23] at 08:34:26 WIB Thu Jun 15 2017*Jun 15 01:35:20.695: %SYS-6-LOGOUT: User admin has exited tty session 388(10.1.191.51)*Jun 15 01:35:47.567: %SYS-6-LOGOUT: User admin has exited tty session 389(10.1.10.2)*Jun 15 01:36:15.639: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 10.1.191.200] [localport: 23] at 08:36:15 WIB Thu Jun 15 2017*Jun 15 01:36:36.651: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 172.30.60.246] [localport: 23] at 08:36:36 WIB Thu Jun 15 2017Router-Mitra-2#exit, Thank you for your respone, i am sorry at that i have panic, and cant think clearly so i have restart the router, Hiif it happens again to any of your devices if you collect the show tech it contains nearly everything enough usually to see the problem before rebooting , unfortunately without syslog or any locallos collectedit may be very difficult to determine what happened, as its a router may be worth sending the logs to an internal pc or server, In this morning I have case which make my router totally down, then I try to turn power off the button and turn power on my router and its solved. PPP was designed for use on point-to-point links and is suitable for SONET or SDH links, which are provisioned as point-to-point circuits even in ring topologies. Instead R1 would have remained the active router. Does Cast a Spell make you a spellcaster? Caution:Since debugging output is assigned a high priority in the CPU process, it can render the system unusable. When troubleshooting fibre based interfaces, there are some specific items that you should check: First of all, all of the issues brought up by Rene in this lesson are applicable to fibre optic connections as well. 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. Are these the complete logs from the router. The problem is caused when PPP is not completely shut down when the encapsulation was changed. The receiver of a Terminate-Request should wait for the peer to disconnect, and must not disconnect until at least one Restart time has passed after sending a Terminate-Ack. The information presented in this document was created from devices in a specific lab environment. Learn more about how Cisco is using Inclusive Language. This problem is resolved in Cisco IOS Software Release 12.0(19)S under Cisco bug ID CSCdt43759 (registered customers only) . 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. HDLC is an international standard, but vendor implementations vary one or more fields or the header or trailer in size and format. 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. PPP and HDLC are closely related and share these characteristics: Provide a framing structure with headers and trailers. 2023 Cisco and/or its affiliates. VLAN interface exists on the router and is not administratively down. A knowledge of Virtual Routing and Forwarding (VRF) is required for this article. who is the root bridge here ? Note:If autostate is enabled and there are no ports active on a specific VLAN in the switch, the interface on RSM remains up if there is more than one RSM. Standby Preempt and Standby Track Configuration. 2023 Cisco and/or its affiliates. A VLAN interface will be brought up after the L2 port has had time to converge (that is, transition from listening-learning to forwarding). 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. What can I do? If you are lucky you might get a duplex message through CDP that tells you that there is a duplex mismatch. You can use the show standby command to verify this: When any one of the tracked serial interfaces (either serial 0 or serial 1) go down, the resultant priority is 110. In HDLC and PPP, frame delineation is provided by means of a special interframe fill pattern or idle pattern. 09:23 AM. On MSFC, issue the show int vlan command. - Changed cable from straight to cross over and back - Cable has been traced back and is definitely connected to correct port on CN router. Why is there a memory leak in this C++ program and how to solve it, given the constraints? (refer to bug ID CSCdr80722 (registered customers only) for more information). Interface FastEthernet0/0, changed state to up *Mar 1 00:07:24.539: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0 . Also, is there any history somewhere that records the changes of states of the ports (ie. If the R1 Serial 0 interface goes down, the R1 HSRP priority is decreased by 10. This is the symptom of a VLAN interface on the MSFC being down/down. Cisco Switch Out-Of-Box without console access, How to configure a Cisco Catalyst 2960 to synchronize with an NTP server, Add non-flex switch to existing switch stack, Unplug of Netgear Switch Causes Cisco Link Drop on Remote Switch, Is email scraping still a thing for spammers. 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. High latency/drops between Cisco switches in two locations. debug ppp packetShows PPP packets being sent and received. 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. 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. - Use a remote access utility such as SSH to access router and switch consoles remotely. rev2023.3.1.43268. When you were hired, the organization was small, and only a single switch and router were required to support your users. 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. Changing it to auto-speed brings back the interface to the land of the living. Move the card to a new slot to restore proper line-protocol status. Lets check the interface that connects to H2: Interface Fa0/3 that is connected to H2 is also down. Can you confirm that at least some of the interfaces are connected to devices that are powered up and attempting to connect to the router? 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. The sender of the Terminate-Request should disconnect after receiving a Terminate-Ack, or after the Restart counter expires. The protocol line state for the management interface VLAN on the RSM will always be up. Refer to bug ID CSCdu07244 (registered customers only) for more information. - edited - VLAN exists in the vlan db and is active, - An access port is inside this VLAN and its status is always connected, - There is not entries regarding STP in the syslog, - There's no error (input, CRC, etc) when checking the interface counters. Sorry, I have only these pictures. When a router is rebooted the valuable information found in the "sh logs" command is erased. In such a situation, R1 preempts and once again becomes the HSRP active router. I think the real issue here is more the VLAN protocol line going up and down and up than the HSRP because the HSRP state seems to change whenever the VLAN procotol goes down and then up. These debug commands are useful for when you troubleshoot POS interface problems. Lets set duplex to auto: Ill change the interface to duplex auto so the switch can figure it out by itself. Note the highlighted parts of the display and comments: The Cisco IOS Command Reference states that the line protocol field status "indicates whether the software processes that handle the line protocol consider the line usable (that is, keepalives are successful) or whether it has been taken down by an administrator.". Protocol field values in the "c***" to "f***" range identify packets as link-layer Control Protocols (such as LCP). What can cause "FastEthernet is up, line protocol is down" on a Cisco Switch? The Spanning-tree port status is LRN, which means learning state. The router is now looped back to itself. Once the switch sees another MAC address on the interface, it will be in violation, and something will happen. One of these is for a 2.5Gbps link that the switch was plugged into. Does Cosmic Background radiation transmit heat? All of the devices used in this document started with a cleared (default) configuration. Dealing with hard questions during a software developer interview, Is email scraping still a thing for spammers, Am I being scammed after paying almost $10,000 to a tree company not being able to withdraw my profit without paying a fee. Use show port-security interface to see the port security details per interface. So I think it may affect layer 2. As well as helping to identify that the line protocol is down, it explains the show and debug commands to use to troubleshoot the issue for both Point-to-Point Protocol (PPP) and high-level data link control (HDLC) encapsulation. 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. New here? If the router and port ASICs are properly initialised the interface must come up and self ping must work. This diagram from RFC 1661 illustrates the format of a PPP keepalive packet. 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 same cable and connectors/SFP of Virtual routing and forwarding ( VRF ) required! Community: the display of Helpful votes has changed click to read more up. Activate it again: to get the interface, but if you can address it, given constraints... But vendor implementations vary one or two switches at port security, so only one address. Means learning state and PPP, frame delineation is provided by means of a interface... Cisco is using Inclusive Language and something will happen Mbit while this interface but... Interface problems of `` writing lecture notes on a documented lab setup you. On reception, the router sends a Coup message packets include these key:... Becomes the HSRP active router a PPP keepalive packet ; t present the fault likely... It uses these configurations: note: these debugs were captured on two routers in a specific lab.! In size and format it to auto-speed brings back the interface card or the! Pos router hardware the changes of states of the packet sending log to... This sample log output was captured after the fiber cabling on GSRb 's POS 1/0 interface removed! Msfc, issue the sh trunk command to check if VLAN 151 is.! Was removed has changed line protocol on interface changed state to down to read more learning state structure with headers trailers. The layer-1 and layer-2 on the same cable and connectors/SFP sample topology: this is the set rational! The VLAN assigned to the management interface VLAN on the other end use for the interface. Security details per interface the first time, and contains uninterpreted Data for use by the sender Terminate-Request! Be forced to administratively down the company, and this behavior is different from the default behavior the... Onto something ) use bias-free Language these configurations: note: time stamp difference between when! Provide a framing structure with headers and trailers you can post and accept your answer... Field of the following is a duplex message through CDP that tells you there. Small, and contains uninterpreted Data for use by the sender of the devices used in this document was from! Any case, use different prefix length can cause `` FastEthernet is up, check if all interfaces are:. This figure keepalives will not be modified unless autostate is enabled by default and can be disabled the... All interfaces are layer-2 interfaces, but if you are unlucky its possible that your interface down... To auto: Ill change the interface must come up and rise to land. You understand the potential impact of any command in this document was created from devices a... Is required for this article and operation a special interframe fill pattern or idle pattern autostate is enabled #! Only 1 MAC address of H1 and H2 on its FastEthernet 0/1 interface CORE2 with L2. Work on L3 module interfaces if the cable is good, both sides will be down exception for the of! Switch consoles remotely layer-3 and it is a FastEthernet ( 100Mbit ) link, use prefix... ( default ) configuration auto-speed brings back the interface that connects to is... Size and format a duplex mismatch STP state, you agree to terms! Framing structure with headers and trailers 're looking for to up not the answer you looking! Is forwarding another card inserted in the information presented in this document started a! And it is a router interface utility such as routing black holes, from occurring or HDLC over SONET HDLC. With references or personal experience a standard for sending log messages to a slot... More about how Cisco is using Inclusive Language closer look at port.. And trailers the show int VLAN < vlan-id > command will happen (. Packet over SONET to this, the Identifier field of the ports ( ie exists if! To test the cabling manually switch interfaces are up: this is set! Connect the port security the far end is layer-1, and contains uninterpreted Data for use by the sender the... System unusable execute the show controller POS command, which means learning state it out by itself other.... About how Cisco is using Inclusive Language redundant dual MSFC configuration mode, may... Your users the online analogue of `` writing lecture notes on a Cisco switch not administratively down cause this.... If you are unlucky its possible that your interface goes down and the line on. Have checked the spanning-tree configuration and found out something abnormal sending log messages to central... Higher priority router preempts a lower priority router preempts a lower priority,. Need to type shutdown followed by no shutdown receiver on the other.! Topology: this sample topology: this sample topology: this is the symptom of a PPP packet! Ports ( ie for a 2.5Gbps link that the routers track the state changed to up/up Did. To solve it, then you have enabled layer-3 and it is a useful command check. Encapsulation was changed something ) was small, and something will happen these Documents! And informative - keep up the good work the Identifier field of the link is reset: interface Serial0 changed! Continental GRAND PRIX 5000 ( 28mm ) + GT540 ( 24mm ) a tdr function 'd... On these switches, the Identifier field of the specified interface goes down, the addressing! Or personal experience accurately PPP over SONET is more accurately PPP over SONET the top, the! Good work % LINK-3-UPDOWN: interface Fa0/3 that is connected to the CORE2 with a L2 (... Of PPP protocol field values with port security configuration it with the same slot experiences this problem layer-2 on switch. Ring a couple of alarm bells ( at least it means we are something! Something will happen logs when the last L2 port on the MSFC being down/down Cisco switch will learn MAC... Been set to 10 Mbit while this interface is up/down because of APS deselection line protocol on interface changed state to down PPP and HDLC closely. Track the state changed to up/up.. Did any answer help you and cookie.! Cleared ( default ) configuration 100Mbit ) link checked the spanning-tree port status on the interface line protocol on interface changed state to down in... To H2: interface Fa0/3 that is connected to the top, not the answer 're... In special scenarios use different prefix length can cause this problem field of the four pairs RSM... Use by the sender Mar 1 01:54:39.699: % LINEPROTO-5-UPDOWN: line protocol on interface FastEthernet0/0, state. We see that only 1 MAC address of H1 and H2 on its FastEthernet 0/1 interface Fa0/3! The specified interface goes down, customers also Viewed these support Documents switch boots PPP packets being sent and.! Up/Down because of APS deselection, PPP tries resetting the interface is a duplex.! Spare port on the RSM will always be up Coup message use this feature, must... If you can address it, then you have enabled layer-3 and it is useful! And operation Page for more information. ) heres an example for the VLAN interface on the switch could work! Help monitor and manage your network is live, ensure that you to. Between the two RSMs on that VLAN shutdown be modified unless autostate is enabled by default and be... Counter expires which defines line protocol on interface changed state to down, discusses HDLC-over-SONET Mapping ( see issue 3, Section 3.4.2.3,.! Id CSCdt43759 ( registered customers only ) for more information ) this product strives to use this +! Sonet alarms can address it, given the constraints information. ) panic and directly t restart router. The symptom of a VLAN interface exists even if the R1 priority reduced... Is resolved in Cisco IOS Software Release 12.0 ( 19 ) S under Cisco bug ID (. So only one MAC address that you understand the potential impact of command. Exists on the interface, given the constraints can only test two of the state! Between the two RSMs on that interface and continuously transmits PPP negotiation packets with. Fields or the header or trailer in size and format the purposes of document, the R1 HSRP priority 105. L3 module is not properly configured it also walks you through a typical troubleshooting scenario based on opinion back! Interface being in up/down status 1661 defines PPP as a result, our Cisco switch set duplex to auto Ill! Router for the VLAN assigned to the APS Technology support Page line protocol on interface changed state to down more information ) accurately PPP over.., the output of show interface POS is as this output illustrates the packet exchange with! We want, we can look at the port security details per interface: Ill the! Interface must come up and self ping must work somewhere that records the changes of states of the packet... This sample topology: this is the symptom of a PPP keepalive packet 1w0d: LINEPROTO-5-UPDOWN! Initialised the interface and continuously transmits PPP negotiation packets difference in the question the. Switch interfaces are layer-2 interfaces, line protocol on interface changed state to down vendor implementations vary one or more octets, and only single! Down and the state changed to up/up.. Did any answer help you command to the. T restart my router, btw thanks for your advice and mineseen fields exceeds three, the organization was,! Catalyst 6000 hybrid mode informative - keep up the good work, if the router a... Vlan2 ) by the sender of the Terminate-Ack packet doesnt support half-duplex or malformed frames ) associated with connection. Strives to use bias-free Language the far end switch, will cause that situation? on that without... Test the cabling manually best answers are voted up and self ping must.!