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Subject: Re: [bug report]scsi: drive letter drift problem
To:     Stefan Hajnoczi <stefanha@redhat.com>
CC:     "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        "Jason Wang" <jasowang@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        <linux-scsi@vger.kernel.org>,
        <virtualization@lists.linux-foundation.org>,
        <linux-kernel@vger.kernel.org>,
        Zhiqiang Liu <liuzhiqiang26@huawei.com>,
        "Wu Bo" <wubo40@huawei.com>, <linfeilong@huawei.com>,
        <yuzhanzhan@huawei.com>
References: <7ae2293e-71a9-f68e-0bfb-b4a70ecf493e@huawei.com>
 <YOwMiYRmGYskOn7A@stefanha-x1.localdomain>
From:   Wenchao Hao <haowenchao@huawei.com>
Message-ID: <8d752421-310f-46d6-fbae-bd72a05d4021@huawei.com>
Date:   Tue, 13 Jul 2021 09:27:12 +0800
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On 2021/7/12 17:34, Stefan Hajnoczi wrote:
> On Mon, Jul 12, 2021 at 12:47:05PM +0800, Wenchao Hao wrote:
>> We deploy two SCSI disk in one SCSI host(virtio-scsi bus) for one machine,
>> whose ids are [0:0:0:0] and [0:0:1:0].
>>
>> Mostly, the device letter are assigned as following after reboot:
>> [0:0:0:0] --> sda
>> [0:0:1:0] --> sdb
>>
>> While in rare cases, the device letter shown as following:
>> [0:0:0:0] --> sdb
>> [0:0:1:0] --> sda
>>
>> Could we guarantee "sda" is assigned to [0:0:0:0] and "sdb" is assigned to
>> [0:0:1:0] or not?
>> If we can, then how?
> Is there a stable ID that you can use in /dev/disk/by-*?
>
> Stefan

Thanks, we found /dev/disk/by-path may be helpful