Welcome to Dell Technologies connect Brocade how to series, how to interpret the Brocade port error show output. And what do the counters mean? Reference de knowledge base article number 037925 and 12010 This video was created to interpret and explain the port error show output. Port errors of Brocade sand switches and possible causes of the errors.
This video presents the following port error show command displays an error summary for a port or a range of ports. Counts are reported on frames transmitted by the port TX or on frames received by the port Rx. The display contains one output line per port numeric values exceeding 999 are displayed in units of thousands K millions M or giga G if indicated when used without operant.
This command displays error summary for all ports on the switch use switch show command for a listing of valid ports, slots and port index numbers. When to do this. When you want to interpret the Brocade port error show output and what each counter means. Port error show command can be used to identify suspect ports to troubleshoot marginal link problems before you begin.
Statistical error depicted in a port error show could be since the last reboot and indicate devices being plugged in or out and set up or configuration work that occurred. Hence use port stats, clear command to clear port statistics and retake data after 4 to 6 hours log into the switch with user having route or administrative privileges. Run the command port air show.
Let us learn about each counter frames, transmitted, the number of frames transmitted by the port frames recede the number of frames received by the port frames, TX and frames Rx is a statistic that provides a baseline for the error counters, encoding errors inside frames.
Words inside of frames are encoded if this encoding is corrupted where an error is detected E and CN is generated minimum compliance with the link bit error rate specification on a link continuously receiving frames would allow approximately one error every 20 minutes for one gigabit per second re initialization.
And reboots of associated N export can also cause these errors frames with cyclic redundancy check errors. The CRC is a four byte field that shall be used to verify the data integrity of the frame header and data field frames that fail A CRC are noted but not modified. And the destination device is responsible for rejecting and we're requesting the frame with good end of frame recede.
When a CRC with a good EF is detected, the switch will tag the frame. So no other port will count the CRC frame and forward the frame on. This allows CRC frame with good EF to be quickly traced to the originating port too short. This counter is increment whenever a frame bounded by start of frame and end of frame is received.
And the number of words between the F and EOF is less than seven words, six words, header plus one word CRC. This could be caused by the transmitter or an unreliable link. Too long FC frames are 2148 bytes maximum. If an EO is corrupted or data generation is incorrect, a too long error is generated.
Eof after a loss of synchronization error, continuous mode alignment allows the receiver to reestablish word alignment at any point in the incoming bit stream. While the receiver is operational, such realignment is likely to result in code violations and subsequent loss of synchronization.
If such a realignment occurs within a received frame detection of the resulting error condition is dependent upon higher level function. Example, invalid CRC missing eo deli encoding error outside of frames. This counter may become a non zero value during link initialization but indicates a problem if it increments faster than the link bit error rate allows approximately once every 20 minutes for one gigabit per second.
Number of class three discard frames discard class three errors could be generated by switch when devices send frames without F lo gig first or with an invalid destination.
Refer to the following. For more information link failures. If a port remains an LR received state for a period of time greater than a time out period, a link reset protocol time out shall be detected which results in a link failure condition, loss of synchronization, synchronization failures on either bit or transmission word boundaries are not separately identifiable and cause loss of synchronization errors, loss of signal occurs when a signal is transmitted but none is being received on the same port fabric port reject frames.
These indicate that the delivery of a frame is being denied. Some reasons for issuing this counter include class not supported, invalid header field and import unavailable fabric port busy frame. This frame is issued by the fabric to indicate that a particular frame cannot be delivered because the fabric or the destination and port is busy.
See three time out TX, the number of transmit class three frames discarded at the transmission port due to time out. C three time out Rx, the number of received class three frames received at this port and discarded at the transmission port due to time out physical coding sub layer block errors.
This counter records encoding violations on 10 gigabits or 16 gigabytes ports. It is equivalent with encoding out errors for eight gigabytes or four gigabits link unc correctable errors. The number of incorrect forward error corrections, important notes loss of sync loss of signal encoding out errors are expected every time user brings the port down and up reboot host power cycle storage, subsystem unplug or plug cable or port disable or port enable.
If the errors rapidly rise. Look for a physical media problem. Statistically encoding out errors alone imply cables encoding out cyclic redundancy check error combo implies GBC or SFP issue. If the error counters continue to rise, move cable to another port. If the problem follows the cable, then suspect a faulty cable or attached media.
If the problem disappears, run cross port test with a loop back plug in online or verbose mode to determine if the GB IC or SFP is faulty for action to be taken when counters increase. Refer Dell knowledge base article how to troubleshoot fiber channel node to switch port or SFP communication problems by means of elimination.
Port error show command is not supported on F ce ports for the Brocade G 620. When encryption is enabled the reserved ports, 44 to 47 will display an error when specified or included as part of a port range. Refer to the following for more information Dell knowledge base article number 037925 and 012010 Brocade fabric OS command reference guide port error show command.
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