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Senior Member
Posts: 1
Registered: ‎05-16-2017

Time TX Credit Zero Problems

Dear all,

 

We have a Dual Fabric Installation 12 Switches per Fabric Core Edge designe.

 

We have problems with 7 total failures since the last 4 months. What we see is the Time TX Credit Zero this rise to over 100 trillion errors after that does not work anymore. Can someone give a tip where this comes from, or how we can the problem anlays.

 

S000PS04:admin> portstatsshow 63
stat_wtx                3290458622  4-byte words transmitted
stat_wrx                64657234    4-byte words received
stat_ftx                1051087673  Frames transmitted
stat_frx                352315019   Frames received
stat_c2_frx             0           Class 2 frames received
stat_c3_frx             352292222   Class 3 frames received
stat_lc_rx              11261       Link control frames received
stat_mc_rx              0           Multicast frames received
stat_mc_to              0           Multicast timeouts
stat_mc_tx              0           Multicast frames transmitted
tim_rdy_pri             5           Time R_RDY high priority
tim_txcrd_z             5459244     Time TX Credit Zero (2.5Us ticks)
tim_txcrd_z_vc  0- 3:  5458943     0           10          37        
tim_txcrd_z_vc  4- 7:  27          227         0           0         
tim_txcrd_z_vc  8-11:  0           0           0           0         
tim_txcrd_z_vc 12-15:  0           0           0           0         
er_enc_in               0           Encoding errors inside of frames
er_crc                  0           Frames with CRC errors
er_trunc                0           Frames shorter than minimum
er_toolong              0           Frames longer than maximum
er_bad_eof              0           Frames with bad end-of-frame
er_enc_out              0           Encoding error outside of frames
er_bad_os               0           Invalid ordered set
er_rx_c3_timeout        0           Class 3 receive frames discarded due to timeout
er_tx_c3_timeout        0           Class 3 transmit frames discarded due to timeout
er_c3_dest_unreach      0           Class 3 frames discarded due to destination unreachable
er_other_discard        0           Other discards
er_type1_miss           0           frames with FTB type 1 miss
er_type2_miss           0           frames with FTB type 2 miss
er_type6_miss           0           frames with FTB type 6 miss
er_zone_miss            0           frames with hard zoning miss
er_lun_zone_miss        0           frames with LUN zoning miss
er_crc_good_eof         0           Crc error with good eof
er_inv_arb              0           Invalid ARB
open                    0           loop_open
transfer                0           loop_transfer
opened                  0           FL_Port opened
starve_stop             0           tenancies stopped due to starvation
fl_tenancy              0           number of times FL has the tenancy
nl_tenancy              0           number of times NL has the tenancy
zero_tenancy            0           zero tenancy
phy_stats_clear_ts      07-19-2017 CEST Wed 12:56:35    Timestamp of phy_port stats clear
lgc_stats_clear_ts      07-19-2017 CEST Wed 12:56:35    Timestamp of lgc_port stats clear

 

Best regards

Ernst

Brocade Moderator
Posts: 284
Registered: ‎08-31-2009

Re: Time TX Credit Zero Problems

Hello,

 

Time TX Credit Zero counter is not an indication of issue.

The recommendation will be to clear all the stats on all the concerned switches.

statsclear;slotstatsclear

 

Then monitor any hardware related issue with porterrshow, portstatsshow as CRC errors, ITW, encoding errors.

Counters below are important to check if free of errors:

 

er_enc_in               0           Encoding errors inside of frames
er_crc                  0           Frames with CRC errors
er_trunc                0           Frames shorter than minimum
er_toolong              0           Frames longer than maximum
er_bad_eof              0           Frames with bad end-of-frame
er_enc_out              0           Encoding error outside of frames
er_bad_os               0           Invalid ordered set
er_rx_c3_timeout        0           Class 3 receive frames discarded due to timeout
er_tx_c3_timeout        0           Class 3 transmit frames discarded due to timeout
er_c3_dest_unreach      0           Class 3 frames discarded due to destination unreachable
er_other_discard        0           Other discards
er_type1_miss           0           frames with FTB type 1 miss
er_type2_miss           0           frames with FTB type 2 miss
er_type6_miss           0           frames with FTB type 6 miss
er_zone_miss            0           frames with hard zoning miss
er_lun_zone_miss        0           frames with LUN zoning miss
er_crc_good_eof         0           Crc error with good eof
er_inv_arb              0           Invalid ARB

 

 

If you see any errors, do necessary investigation with your OEM and report issue seen with supportsaves.

Do you have already monitoring tools in place as MAPS or BNA?

 

Any and all information provided by me is not reviewed, approved or endorsed by Brocade and is provided solely as a convenience for Brocade customers. All systems and all networks are different and unique. If you have a service affecting network problem, please open a TAC service request for service through Brocade, or through your OEM equipment provider. If this provided you with a solution to this issue, please mark it with the button at the bottom "Accept as solution"

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