未配置环回，执行码流测试或诊断时报错-8005、-8001

问题现象

[****@******]# ascend-dmi --dg -i prbs -q
Summary:
    Arch: aarch64
    Mode: *****
    Time: 20250414-15:16:43

Hardware:
    prbs:
        FAIL
        *** error occured on device 0
        *** error occured on device 1

查看日志，报错如下。

[WARN][2025-04-14 15:15:46][76270][prbs_thread.cpp ControlTransPrbsCodeStream:86] call dcmi_prbs_operate failed. type=8, direction=1, cardId=3, chipId=0, ret=-8005
[WARN][2025-04-14 15:15:46][76270][prbs_thread.cpp ExecPrbsCodeStream:229] start prbs trans failed on device 3
[WARN][2025-04-14 15:15:47][76270][prbs_thread.cpp ControlTransPrbsCodeStream:86] call dcmi_prbs_operate failed. type=8, direction=1, cardId=6, chipId=0, ret=-8001
[WARN][2025-04-14 15:15:47][76270][prbs_thread.cpp ExecPrbsCodeStream:229] start prbs trans failed on device 6

可能原因

驱动版本在25.0.RC1及以上，未配置环回，开启打流时校验SNR不通过。

解决措施

配置CDR环回或外接光纤回路器，待网口up后，重新执行打流操作。