Chris's Wiki :: blog/linux/LinuxGPTAndEFI Commentshttps://utcc.utoronto.ca/~cks/space/blog/linux/LinuxGPTAndEFI?atomcommentsDWiki2011-12-06T02:07:01ZRecent comments in Chris's Wiki :: blog/linux/LinuxGPTAndEFI.From 12.94.77.210 on /blog/linux/LinuxGPTAndEFItag:CSpace:blog/linux/LinuxGPTAndEFI:cd4621be11904e72d12f8a2feebf261943f9f75fFrom 12.94.77.210<div class="wikitext"><p>If you want some real pain, try UEFI booting across a network!</p>
<p>On the very expensive blade servers I work on the network cards will do the DHCP dance and download a program. However the environment that they drop you into no longer seems to know which card did the dance, and so you have no way to get any more information, like say a configuration file from your server.</p>
<p><a href="https://bugzilla.redhat.com/show_bug.cgi?format=multiple&id=670266">https://bugzilla.redhat.com/show_bug.cgi?format=multiple&id=670266</a></p>
<p>has some more information.</p>
</div>2011-12-06T02:07:01ZFrom 208.54.39.156 on /blog/linux/LinuxGPTAndEFItag:CSpace:blog/linux/LinuxGPTAndEFI:7a276ec1d78f27d28a87c18387ba30e5e5039510From 208.54.39.156<div class="wikitext"><p>Actually, I take that back—you <em>do</em> need some tricks for older BIOSes. One of them is a "hybrid" MBR. You can create one with gdisk; by default, it creates a "protective" one (as indicated in my listing above).</p>
<p>— <a href="http://blog.samat.org">Samat</a></p>
</div>2011-12-04T07:56:25ZFrom 208.54.39.156 on /blog/linux/LinuxGPTAndEFItag:CSpace:blog/linux/LinuxGPTAndEFI:f9ba31d105dc01b28637bf65437e49670a10bf98From 208.54.39.156<div class="wikitext"><p>I've noticed that most BIOSes since 2007 boot GPT disks without issue, not just MBR disks. I've yet to encounter a machine where UEFI worked well.</p>
<p>I'm using GPT on my ThinkPad X61t w/ SSD (partitions are aligned to 4K sectors and all that), booting w/ GRUB2. Works great. 4 MB is overkill for the BIOS boot partition; I use a little under 1 MB left over from aligning partitions. Here's my table:</p>
<pre>
$ sudo gdisk -l /dev/sda
GPT fdisk (gdisk) version 0.8.1
Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present
Found valid GPT with protective MBR; using GPT.
Disk /dev/sda: 78165360 sectors, 37.3 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): D6482B5A-574E-04BF-D56F-6825009EB825
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 78165326
Partitions will be aligned on 8-sector boundaries
Total free space is 6 sectors (3.0 KiB)
Number Start (sector) End (sector) Size Code Name
1 40 2047 1004.0 KiB EF02 EFI System
2 2048 16779263 8.0 GiB EF00 EFI System
3 16779264 57192447 19.3 GiB 0700 Linux/Windows data
4 57192448 78165326 10.0 GiB 0700 Linux/Windows data
</pre>
<p>Yeah, I need to get around to writing this up in a series of blog posts…</p>
<p>— <a href="http://blog.samat.org/">Samat</a></p>
</div>2011-12-04T07:52:10Z