Arch Linux

Cape

Member

From: Mogliano Veneto, Italy

Registered: 2008-11-15

Posts: 105

grub can't boot jfs - possible solutions

Hi all!

Basically, after a kernel and various other paks update, grub stopped booting my jsf partition containing everything except  /var & /usr...
So, first i read about this incompatibility just weeks after it happened! There's no clue about this neither in the official install guide or in the grub wiki or anything else... anyway. The problem now is that I already have 4 primary partitions:

sda1 windlorws

sda2  /boot ex... (JFS)

sda4 [EXTENDED]
      sda5 /var (reiserfs)
      sda6 swap
       [/EXTENDED]

sda3 windlords rescue partition

So, since i can't shrink sda2 to fit into the extended partition and i can't create another primary partition... i see the only possible solution is to convert sda2 to another bootable fs.

Am i right?

And if so, how is ext4? I saw a benchmark and seems to be just slightly slower than JFS but i'm pretty scared about the loss of data after hard shut down... Is it a concrete thread? Any other possible FS?

Last edited by Cape (2009-10-01 15:35:59)

samjh

Member

From: Australia

Registered: 2009-08-25

Posts: 34

Website

Re: grub can't boot jfs - possible solutions

I'm a long-time JFS user who switched to ext4 when it was first released.  Over-all, it's a good FS, but I think (just my perception) that JFS seems to be more efficient when copying large files than ext4.

For safety, I think they are comparable.  Don't be too concerned about the data-loss issue with ext4.  All delayed-allocation journalling file systems suffer from the same problem ext4 had (including JFS, XFS, and others).  The issue isn't the file system, but application software that have not been programmed to write data to disk properly.  For ext3, the Linux kernel wrote changes to disk at more frequent intervals than other delayed-allocation journalled file systems (actually a flaw of sorts), and some application programmers relied on it too much.  There is more to it than that, but that is the simplest explanation I can give.

Ext4 is fine.  The kernel was patched several months ago so that the delay interval for ext4 is the same as ext3 (albeit with reduced performance for ext4 than designed).

Cape

Member

From: Mogliano Veneto, Italy

Registered: 2008-11-15

Posts: 105

Re: grub can't boot jfs - possible solutions

mmm ok than... I'll give it a try. By the way, are there any hazards when converting a file system? How long does it take?

Inxsible

Forum Fellow

From: Chicago

Registered: 2008-06-09

Posts: 9,183

Re: grub can't boot jfs - possible solutions

mmm ok than... I'll give it a try. By the way, are there any hazards when converting a file system? How long does it take?

It is always hazardous when mucking with file systems if you dont know what you are doing. Take proper precautions and you should be fine. As always, backup any data that you might want to keep.

The time depends on how big the drive is and what file system you have chosen to format it to.

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Cape

Member

From: Mogliano Veneto, Italy

Registered: 2008-11-15

Posts: 105

Re: grub can't boot jfs - possible solutions

But basically, what i have to do is copying the whole partition somewhere safe, format to ext4, re-recopy everything in the new part, edit fstab, and re-install GRUB... am i right?

iBertus

Member

From: Greenville, NC

Registered: 2004-11-04

Posts: 2,228

Re: grub can't boot jfs - possible solutions

I'm using ext4 here on both of my machines and it works fine. Before I used JFS and loved it but switched when I started using LVM+RAID. ext4 supports resizing volumes more completely than JFS ever will.

Inxsible

Forum Fellow

From: Chicago

Registered: 2008-06-09

Posts: 9,183

Re: grub can't boot jfs - possible solutions

snip... ext4 supports resizing volumes more completely than JFS ever will.

That was always one of the advantages of going with EXTn. and knowing me.... I always kept playing around with the partition sizes initially. Now though, I am satisfied with what I have, but I still keep Ext3 or Ext4 for / and /home. Reiserfs for /var. and ext2 for /boot

Last edited by Inxsible (2009-10-08 19:33:38)

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Cape

Member

From: Mogliano Veneto, Italy

Registered: 2008-11-15

Posts: 105

Re: grub can't boot jfs - possible solutions

yes I'm totally switching to LVM to. Plus this problem made me think a lot about data security... i'm totally backing-up my data asap ;-) .