duplicate DoC millenium with dd

Nikolai Vladychevski niko at isl.net.mx
Tue Sep 11 16:58:53 EDT 2001


David Woodhouse writes: 


> 
>> > What are you partitioning it for, btw?
>> It's a firewall. I place linuxbios & kernel first, then I nftl_format
>> /dev/mtd0 0xFIRST_FREE_BLOCK and place a minimal filesystem (cramfs)
>> on the  rest of the chip.....
> 
> You nftl_format it with the offset, which gives you a block device /dev/
> nftla. Then you use sfdisk rather than mkcramfs -o /dev/nftla. If you only 
> have one partition, then a partition table is just a waste of space.

right! thanks, didn't note it.... 

>  
> 
>> since you say nftl_format removes
>> original badblocks  table M-Systems put on the chip at fabrication
>> time, I kinda dislike this  util..... 
> 
> It's now better than it was. And you shouldn't need to use it more than 
> once, if the total size of your LinuxBIOS and kernel don't change (or if 
> you left enough space for a little bit of expansion).

yes, this is the problem... right now I'm leaving 1 Meg for the linuxBIOS 
and kernel and right now there is left as little as 40 K bytes free space of 
that meg. 

I beleive the kernel will grow very soon and 40 K will not be enough. 
Allocating more space, 1.5Meg for example seems to be a huge waste of space.
I think I will have to nftl_format with a variable offset every time I do an 
update..... you say nftl_format is better, but how much? If I update the 
software on the chip once a week (it's an automatic update via remote 
server), will it survive for 2 years without errors, for example ? 

> 
>>  is there any way to avoid nftl_format and boot my cramfs from /dev/
>> mtdblockX  or /dev/mtd0 with an 0xXXXX offset or something like this? 
> 
> Not out of the box. It's trivial to do that though, by using the mtd
> version of partitions, which makes it look like two (or more) separate MTD
> devices. 

Wow! that sounds cool! I have to try it, but would linuxBIOS conflict with 
it? 


Nikolai 




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