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I've got a problem with my 3G modem [Huawei E122]. It has internal storage and kernel assigns a device [/dev/sdX] to it. Because of that, every second time my machine will not boot - kernel panic - as my usb hdd gets assigned /dev/sdb instead of /dev/sda. I cannot use LABEL nor UUID in root= kernel parameter, as it is only available when using initrd, and I can't use it - I am using Debian on my router - mips architecture machine. I have to prevent this from happening, as my router has to start everyday and I have to be sure it works ok. I don't have physical access to restart it when something goes wrong. I don't use my modem internal storage, there's no SD card inserted. However kernel detects the reader and loads it. I can not prevent loading od usb drivers since my hdd is on USB as well.

I will appreciate any ideas.

share|improve this question – user81793 May 18 '11 at 12:37
up vote 0 down vote accepted

You need to disable the "ZeroCD" feature, which can be done with "usb_modeswitch", available for Debian.

See the man page for more details.

share|improve this answer
Yes, that's actually how I did it. – Krystian May 19 '11 at 6:32
You should add in your answer how to do that. – Francisco Tapia Sep 30 '15 at 14:59

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