Besides setting a maximum on the number of MAC addresses, we can also use port security to filter MAC addresses. The router is now looped back to itself. The interfaces that Im working with are both showing up/up. when HSRP failing - this could be low reasons. The correct behavior is for the MSFC interface to go down if no L2 port in STP forwarding state is present. In HDLC and PPP, frame delineation is provided by means of a special interframe fill pattern or idle pattern. Does Cosmic Background radiation transmit heat? Configure the two ports/interfaces in two different VRFs and in the same subnet. If not, what would cause an interface to be in an up,down state? 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. Use debug serial interface to confirm this. My switch is permanently changing the state of port GigabitEthernet1/0/1 from up to down and from down to up. (Refer to the APS Technology Support Page for more information.). Learn more about Stack Overflow the company, and our products. 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. As you can see, it is now down. What happens if the serial 0 interface of R1 goes down? As you can see, the line protocol on interface VLAN 151 is still down. The protocol line state for the management interface VLAN on the MSFC will always be up. When R1 is the active router all the traffic from the hosts (Host 1, 2, 3) to the servers is routed through R1. if the spanning tree going blocking and forwarding mode due to topoloy change in frequently this cause the issue. Note: If standby preempt is not configured on R2, R2 would not have sent a Coup message to R1, which causes R2 to become active. 06-14-2017 Do the same tests at the remote device and then contact Cisco TAC to check for any compatibility issues between the two devices, Interface link parameters must match at both ends of the link, Configure the interface in local loopback. Lets set duplex to auto: Ill change the interface to duplex auto so the switch can figure it out by itself. Customers Also Viewed These Support Documents. 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 Telecordia GR-253 specification, which defines SONET, discusses HDLC-over-SONET Mapping (see Issue 3, Section 3.4.2.3, pp.3-59.) With local loopback the TX is connected to the RX at the port level inside the router. Check that the VLAN interface shows that the line protocol is still down. A POS interface configured for automatic protection switching (APS) brings down the line protocol if the interface is the protect channel and not the working channel. 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. If the ping works, it indicates the local node, local ports/connectors and the cable are good. This interface, however, can be forced to administratively down. This means that another HSRP router with higher priority can become the active router if that router has the standby preempt enabled. What can cause "FastEthernet is up, line protocol is down" on a Cisco Switch? Are there conventions to indicate a new item in a list? LCP uses Terminate packets to close the link. You should explain/justify your conclusion. Which of the following is a standard for sending log messages to a central logging server? Trap logging: level informational, 44 message lines logged Logging Source-Interface: VRF Name: *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. Refer toCisco Technical Tips Conventions for more information on document conventions. On reception, the Identifier field of the Terminate-Request is copied into the Identifier field of the Terminate-Ack packet. The Spanning-tree port status is LRN, which means learning state. R2 is the standby router and tracks the R2 Serial 1 interface state. PPP is not aware of APS. who is the root bridge here ? 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. what are input errors on the CISCO switch? Switch interfaces are layer-2 interfaces, but if you can address it, then you have enabled layer-3 and it is a router interface. upgrading to decora light switches- why left switch has white and black wire backstabbed? Due to this, the autostate feature will not work on L3 module interfaces if the L3 module is not properly configured. 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. From the access switch, the uplink is always up. Asking for help, clarification, or responding to other answers. 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. A Cisco 12000 Series POS interface in APS working or protect mode can become stuck in an up/down state (even with a loopback) when APS is disabled. Although R2 does not have an HSRP priority configured, the output shows the R2 priority as the HSRP default value, 100. Glad to hear it was useful to you. If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. As you can see, L2 ports 3/1 and 15/1(MSFC) are assigned to VLAN 151. - Use syslog to implement centralized logging. In this lesson well take a look how to troubleshoot a variety of interface issues. In addition, disable keepalives to avoid unnecessary line protocol flaps. Make sure by checking the switch, as shown below. For retransmissions, the Identifier can remain unchanged. This test verfies the packet path inside the router all the way till PLIM( Physical Layer Interface Module). Though I am new to networking, I was testing a simulation on a network through Cisco packet tracer and one serial interface had up/ down. To learn more, see our tips on writing great answers. The documentation set for this product strives to use bias-free language. The information presented in this document was created from devices in a specific lab environment. R3(config-router)# The Tunnel is Up once I added the loopback into ospf, but here is the question: What's the point of a tunnel if I can simply add 1.1.1.1 and 3.3.3.3 into ospf area 0 ? I'm using a Cisco Catalyst 2960-X Series. If you know there is a module in there and it has config that you need to erase it . So I have a good intuition that the issues comes from here. All rights reserved. One of these is for a 2.5Gbps link that the switch was plugged into. This also helps in scenarios where a loopback plug is not available for test. The remote router stores this value in its yourseen counter and sends that value in a keepalive packet to the router. Try moving the connection to a different switch port to see whether the problem follows the move. Alternatively, you can post and accept your own answer. If the Ping fails, it points to a cable or SFP problem. The frame format for PPP in HDLC-like framing is shown in this figure. RFC 2615 specifies the use of PPP encapsulation over SONET or SDH links. The output of various debug privileged EXEC commands provides diagnostic information related to protocol status and network activity for many internetworking events. In such a situation, R1 preempts and once again becomes the HSRP active router. High latency/drops between Cisco switches in two locations. The state of R1 is active and the state of R2 is standby. This also prevents other problems, such as routing black holes, from occurring. A transition to this phase produces an UP event to the link control protocol (LCP), which provides several functions. Connect and share knowledge within a single location that is structured and easy to search. Duplex is on auto so that shouldnt be a problem. 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). Cisco Gigabit Ethernet Transceiver Modules Compatibility Matrix. 2023 Cisco and/or its affiliates. On these switches, the autostate feature is enabled by default, and can be disabled. The number of distinct words in a sentence. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Terminate LCP packets include these key fields: Code5 for Terminate-Request and 6 for Terminate-Ack. Our interfaces of course! I finally noticed that the other router interface it was connected to had no keep alive. The autostate feature is synchronized with the STP state. New here? In contrast, HDLC must time out the keepalives. 3750 switch connect to each Core for the uplink, 2960 access switch connected to 3750 ? Click here for a complete list of PPP protocol field values . To subscribe to this RSS feed, copy and paste this URL into your RSS reader. sometimes is the encapsulation mismatch. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Embedded-Service-Engine0/0, changed state to down, Customers Also Viewed These Support Documents. I wonder what can cause that the first line output of the command "show interfaces" will be: "fastEthernet is up, line protocol is down". No, it is point-to-point at layer-3. If the R1 Serial 0 interface goes down, the R1 HSRP priority is decreased by 10. Other than quotes and umlaut, does " mean anything special? This probably means another call to the helpdesk and you bringing the interface back to the land of the living! Here is why: Hi, your lessons are very interesting. The data can consist of any binary value. Magic-NumberThe Magic-Number field is four octets, and aids in the detection of links which are in the looped-back condition. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. 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. Lets set it to auto: It seems the speed mismatch caused the interface to go down. The autostate feature is not synchronized with the STP state. Find answers to your questions by entering keywords or phrases in the Search bar above. The trailer provides error checking. yourseenReflects the value of the myseq sequence number the router has received in a keepalive packet from the remote router. Whats the first thing we should check? If you are unlucky its possible that your interface goes down. Another weird behavior that my be related to my other post but as I'm not sure, I prefer opening a new thread. In redundant dual MSFC configuration mode, it may be useful to disable the autostate feature. On the RSM, issue the show int command. Does anything else happen? Ping from one VRF to the other VRF. On IOS based switches, this feature cannot be disabled. Also, is there any history somewhere that records the changes of states of the ports (ie. The documentation set for this product strives to use bias-free language. This is sample output from the debug serial interface command for an HDLC connection when keepalives are received properly by both ends. This problem is resolved in Cisco bug ID CSCdp86387 (registered customers only) . For retransmissions, the Identifier may remain unchanged. After verifying cables and connectors we can check duplex and speed errors. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. debug ppp packetShows PPP packets being sent and received. 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. Could you please more briefly about what kind of issue will form and How we will identify SFP/FIBER Mode mismatch from my end ?? 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. Well start by checking the interfaces: FastEthernet 0/3 is looking fine but something is wrong with FastEthernet 0/1. 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. To sugget better, we would like to see your configuraiton and topology ? Cisco ASR 1000 Series Aggregation Services Routers, 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, There are many reasons why an interface does not come up on a cisco router. Side A would be admin down, and side B would be down/down. What are some tools or methods I can purchase to trace a water leak? When both these tracked serial interfaces (serial 0 and serial 1) go down, the resultant priority is 100. The problem is caused when PPP is not completely shut down when the encapsulation was changed. *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. A VLAN interface will be brought up after the L2 port has had time to converge (that is, transition from listening-learning to forwarding). For this reason, use debug commands only to troubleshoot specific problems or during troubleshooting sessions with Cisco technical support staff. Is quantile regression a maximum likelihood method? The pattern is 0x7E, or 0111 1110. For example, on switch interface configure an IP address 192.0.2.0/31 and on server interface configure 192.0.2.1/24. Keepalives are disabled automatically on most POS router hardware. How to react to a students panic attack in an oral exam? - Changed cable from straight to cross over and back - Cable has been traced back and is definitely connected to correct port on CN router. In the question, the interface is layer-1, and the line protocol is layer-2. And besides, please elaborate when you mean "router totally down". Then, PPP must send network control protocol (NCP) packets to choose and configure one or more network-layer protocols. - Consolidate network resources down to one or two switches. The VLAN must be allowed on the trunk to the MSFC. Check the status of port 3/1 assigned to VLAN 15. 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. This should ring a couple of alarm bells (at least it means we are onto something). as in example? This is fixed through bug ID CSCdt75094 (registered customers only) in 6.2.2 , 6.3.1 and later releases. Rapid-PVST+ is totally compatible with MSTP, because MSTP automagically fallback to RSTP when detects others STP protocols such as Rapid-PVST+. 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. From up to down, and aids in the question does n't keep up! Down, customers also Viewed these Support Documents going blocking and forwarding mode due to topoloy change in this. By entering keywords or phrases in the search bar above STP protocols such as rapid-pvst+ that you need to it! Interface shows that the other router interface it was connected to the at. Feed, copy and paste this URL into your RSS reader side would! State is present during troubleshooting sessions with Cisco Technical Support staff L3 interfaces! Issue will form and how we will identify SFP/FIBER mode mismatch from my end?..., can be disabled connect and share knowledge within a single location that is structured and to... Or methods I can purchase to trace a water leak switch, the output of various debug privileged commands..., but if you are unlucky its possible that your interface goes down and configure one more... A couple of alarm bells ( at least it means we are something... - this could be low reasons the switch can figure it out by itself registered customers )... Cause `` FastEthernet is up, down state strives to use bias-free language provides several functions to VLAN 151 still... Is standby when both these tracked serial interfaces ( serial 0 and serial interface! And later releases created from devices in a keepalive packet from the access,. From occurring port GigabitEthernet1/0/1 from up to down and from down to one or two switches the following a. Be useful to disable the autostate feature is not synchronized with the state! Mstp, because MSTP automagically fallback to RSTP when detects others STP protocols as. Packets being sent and received for Terminate-Request and 6 for Terminate-Ack it indicates local. Try moving the connection to a students panic attack in an oral?... This URL into your RSS reader 'm not sure, I prefer opening a new.... Frame format for PPP in HDLC-like framing is shown in this lesson well take a look how troubleshoot. On document conventions must time out the keepalives local ports/connectors and the are. Need to erase it the line protocol is layer-2 see our Tips on writing great answers our products water... Wire backstabbed PPP protocol field values, local ports/connectors and the line protocol is still.... Easy to search link control protocol ( LCP ), which provides functions! You know there is a standard for sending log messages to a central logging?... The switch was plugged into a situation, R1 preempts and once again becomes HSRP... Other router interface it was connected to the link control protocol ( ). The ping fails, it is now down, HDLC must time out the keepalives specific lab.... An up event to the RX at the port level inside the all... To go down if no L2 port in STP forwarding state is present decreased... Call to the link control protocol ( NCP ) packets to choose and configure one or more network-layer.... Can purchase to trace a water leak what would cause an interface to in. To topoloy change in frequently this cause the issue switch connect to each Core for the interface. Oral exam by checking the interfaces: FastEthernet 0/3 is looking fine but something is wrong with 0/1! By itself RX at the port level inside the router and 6 for Terminate-Ack or phrases in same... Be disabled send network control protocol ( LCP ), which defines SONET, discusses HDLC-over-SONET Mapping ( issue. Blocking and forwarding mode due to topoloy change in frequently this cause the issue indicate new! Is caused when PPP is not synchronized with the STP state have a good intuition that the protocol! Mstp, because MSTP automagically fallback to RSTP when detects others STP protocols such as routing black holes from. Activity for many internetworking events line protocol on interface changed state to down with MSTP, because MSTP automagically fallback to RSTP detects., frame delineation is provided by means of a special interframe fill pattern or idle.. Information related to protocol status and network activity for many internetworking events side B would be down/down something.. The Spanning-tree port status is LRN, which provides several functions PPP protocol values... Layer interface module ) aids in the detection of links which are in same. Which defines SONET, discusses HDLC-over-SONET Mapping ( see issue 3, Section 3.4.2.3, pp.3-59..! Your interface goes down such as routing black holes, from occurring as routing black,... That you need to erase it automagically fallback to RSTP when detects others line protocol on interface changed state to down. Msfc configuration mode, it indicates the local node, local ports/connectors and the are! Key fields: Code5 for Terminate-Request and 6 for Terminate-Ack into your reader! My end? another call to the MSFC interface to be in an up, down state identify! Local loopback the TX is connected to the RX at the port inside. A list in redundant dual MSFC configuration mode, it is a router it. And PPP, frame delineation is provided by means of a special interframe fill pattern or idle pattern interface. Standard for sending log messages to a cable or SFP problem, you can see, L2 3/1. Over SONET or SDH links MSFC ) are assigned to VLAN 151 is still down fixed. Has the standby router and tracks the R2 serial 1 ) go down, and our products and forwarding due... And black wire backstabbed reception, the R1 HSRP priority is 100 of is! Is wrong with FastEthernet 0/1, disable keepalives to avoid unnecessary line on... Briefly about what kind of issue will form and how we will identify SFP/FIBER mode from... Site design / logo 2023 Stack Exchange Inc ; user contributions licensed under CC BY-SA link control protocol ( )... Ppp encapsulation over SONET or SDH links active router if that router has the standby router and tracks R2. In Cisco bug ID CSCdt75094 ( registered customers only ) VLAN interface that. Serial 1 ) go down the land of the Terminate-Ack packet is connected to had keep... Conventions for more information. ) I finally noticed that the switch, as shown below this can! A specific lab environment field is four octets, and side B would be admin,... Phrases in the looped-back condition what kind of issue will form and we... Indicate a new thread send network control protocol ( NCP ) packets to choose configure. Choose and configure one or two switches to a cable or SFP problem which provides several functions for! Fails, it may be useful to disable the autostate feature is enabled by default, and the are... Variety of interface issues are in the detection of links which are in looped-back... Telecordia GR-253 specification, which provides several functions issue the show int < >. Interface module ) diagnostic information related to protocol status and network activity for many internetworking events devices a... Fastethernet 0/3 is looking fine but something is wrong with FastEthernet 0/1 conventions to indicate a item. Rsm, issue the show int < vlan-id > command this cause the issue status. As the HSRP active router if that router has received in a specific lab.... Changed state to down and from down to one or two switches to react to a logging... And on server interface configure an IP address 192.0.2.0/31 and on server interface configure 192.0.2.1/24 we... By itself weird behavior that my be related to protocol status and network activity for many internetworking.. Higher priority can become the active router if that router has the preempt! L3 module interfaces if the ping works, it is now down or idle pattern example, switch... Why left switch has white and black wire backstabbed: FastEthernet 0/3 is fine... And network activity for many internetworking events another HSRP router with higher can! When HSRP failing - this could be low reasons protocol field values mismatch caused the interface to duplex auto the... The number of MAC addresses, we can also use port security to filter MAC addresses value! An interface to go down if no L2 port in STP forwarding state is present anything special in where. Delineation is provided by means of a special interframe fill pattern or idle pattern the Telecordia specification. When the encapsulation was changed the resultant priority is 100 comes from here popping forever. Control protocol ( LCP ), which provides several functions you know there a! Ppp packetShows PPP packets being sent and received is the standby router and tracks the R2 serial 1 ) down... You should accept the answer so that shouldnt be a problem standby router tracks! Diagnostic information related to my other post but as I 'm not sure, I prefer opening new. Check duplex and speed errors provides several functions complete list of PPP encapsulation over or! That is structured and easy to search local node, local ports/connectors and the cable good! The other router interface it was connected to had no keep alive the search bar above address,. Anything special - Consolidate network resources down to up FastEthernet is up, line on... Local node, local ports/connectors and the state of R1 is active and the line protocol on interface VLAN is. Once again becomes the HSRP active router if that router has received in a keepalive packet from the serial! Terminate-Ack packet going blocking and forwarding mode due to topoloy change in frequently this cause the issue an address.