Description of the problem

An operator has recently experienced frequent COMMUN_FAIL reports from multiple N4SL64s, which were resolved after replacement.

Device Type: OSN3500

Version type: 5.21.18.50P01

Alarm information

N4SL64 frequently reported COMMUN_FAIL

Processing

Solution:

1, network element upgrade: the entire individual network element upgrade to V1R8C02SPC500, you can circumvent this problem;

2, single-board upgrades: a separate upgrade N4SL64 circuit board to 8.01, that is, the weak matching, can also solve this problem, and this weak matching is feasible.

3, single-board replacement: the SSN4SL64 replaced with N1 or N2 lines

The present network is solved by upgrading the single board separately.

Root Cause

1, after confirming, N4SL64 in the detection of 485 communication with error code, circuit board to carry out their own reset, resulting in an alarm;

The black box record can be seen: (bb5 record)

1834 2012-5-28 11:14:19 0xB033 VSEND:Malloc error 20030036

1835 2012-5-28 11:19:29 0xB033 VSEND:Malloc error 20030036

1836 2012-5-28 12:20:59 0xB033 VSEND:Malloc error 20030036

1837 2012-5-28 15:17:31 0xB033 VSEND:Malloc error 20030036

1838 2012-5-28 16:54:6 0xB033 VSEND:Malloc error 20030036

1839 2012-5-29 0:15:9 0xB033 VSEND:Malloc error 20030036

2, first of all, 485 error code is unavoidable, by the inter-board interference and other factors will be generated in the detection of error code will be retransmitted, but the N1 and N2 will not be reset, while the N4SL64 circuit board to detect error code on the reset, the handling of the mechanism is flawed, need to be resolved in the code ;

Suggestions and summaries

1, NG equipment some weak matching is tested in the laboratory, this case N4SL64 (8.01) with 18.50p01 use is laboratory tested. This tested weak matching scenario is the same as the normal release matching scenario. (It can be understood as a matching use);

2, N4SL64 veneer belongs to the R10 development of vertical replacement veneer, is backward compatible, for the R8 version does not have a strong supporting argument, so in this case, the separate upgrade circuit board to 8.01 is no risk.

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