udev: missing sysfs features

DONAHUE · Posted: Sat Jul 17, 2010 1:56 pm Post subject:

to end the sysfs error, reconfigure the kernel:

odeSolver · Posted: Sat Jul 17, 2010 1:58 pm Post subject:

DONAHUE · Posted: Sat Jul 17, 2010 2:05 pm Post subject:

change that to:

odeSolver · Posted: Sat Jul 17, 2010 2:17 pm Post subject:

OK. I did what you said. But did you leave out a column? Should it have been this?

DONAHUE · Posted: Sat Jul 17, 2010 2:34 pm Post subject:

See the extra slash in there? --> They look the same here. It's good.

I have moved passed that part of the install and I'm not sure how it will effect things. --> It won't affect things; Independent of other steps. OK to skip, sysfs error seems harmless, just annoying.

section 7.e of the Install Handbook --> Skip it, needed in 2006, udev now takes care of it functionally.

odeSolver · Posted: Sat Jul 17, 2010 3:47 pm Post subject:

DONAHUE · Posted: Sat Jul 17, 2010 4:17 pm Post subject:

It seems my CDRom is being mounted as readonly. I have write capability on it. Should I remove the ",ro" on the /dev/cdrom? --> I don't use the cdrom line in fstab, udev automount has problems with it

Do I need "config_eth0=( "dhcp" )" in /etc/conf.d/net? I think not, but am not sure from the documentation. Note that networking worked "out of the box" for the LiveCD and that I'm using the gentoo-sources kernel (which is the same as the LiveCD kernel). --> No, if it is otherwise empty or all comments. You will need to emerge a dhcp/dhcp client; covered in handbook. Networking will require no setup if wired and using dhcp. You may need to add driver(s) in kernel though.

My hosts file has a strange looking line which is not mentioned in the handbook:
Code:
::1 localhost --> for ipv6

I think that will not be a problem. Am I right? --> right

In /etc/conf.d/clock, how do I know if my hardware is using UTC. From the install handbook: --> Did you set clock in BIOS to GMT (UTC) or to your local time?
Quote:
If your hardware clock is not using UTC, you need to add CLOCK="local" to the file.

If my hardware is not using UTC, do I add this line, in addition to the one that says CLOCK="UTC", as the handbood says, or replace "UTC" with "local"? --> replace

I'm currently emerging syslog-ng. If I later decide to go to a different logger - or no logger at all - is there away to unemerge it? That is, to delete all extraneous files that are no longer needed once it's uninstalled? --> Yes
emerge --unmerge syslog-ng removes the package and obvious orphan packages; emerge -av --depclean (which requires great caution in use) finds and removes orphan packages if the unmerge leaves some.

odeSolver · Posted: Sat Jul 17, 2010 5:27 pm Post subject: Yet more questions

BradN · Posted: Sat Jul 17, 2010 5:48 pm Post subject:

I believe adding config_eth0=( "dhcp" ) in /etc/conf.d/net removes an extra message that appears during boot saying a default was used for the configuration, but it's just cosmetic.

I don't think the ro option has any effect in fstab for cdroms (they're read-only anyway but may be a hint to desktop environments that the device is always read only), unless you happen to use a UDF formatted RW disc (or an uncommon dvd-ram disc) - this is the only way a cd/dvd can be written from the filesystem (otherwise a cd burning program uses a different mechanism that bypasses /etc/fstab for this). Writing to UDF formatted discs is awkward and formatting them only works with older drives (linux apparently doesn't have a utility that supports the command newer drives use to do this).

I don't know how udev/hal works with automounting and how a /etc/fstab entry for the cd relates to it - I don't use automounting.

If you decide to add a swap file, you'd re-add the swap line (assuming /swap is the location you created it at) as:
/swap none swap sw 0 0

Clock: If you're dual booting with windows, you must use "local" - windows doesn't support hardware clock with UTC (but it certainly should support this - it makes more sense and solves daylight savings time confusion since the hardware clock can be unchanged for daylight savings and the OS returns the correct time automatically according to the day of year). There's no good way to handle daylight savings with local time and more than one OS - either they both try to change it and it'll be off an hour, or one changes it but the other OS's time is off by an hour until you boot into the one that changes it. Of course Microsoft doesn't want you running another OS to start with. What a mess.

The extra ::1 localhost line in /etc/hosts is only there for IPv6 support - if you don't use IPv6 it won't have any effect.

DONAHUE · Posted: Sat Jul 17, 2010 5:57 pm Post subject:

dns_domain_lo="jeffnet" --> delete it, it will cause /etc/resolv.conf to be overwritten with garbage

Should I follow the handbook instructions for installing grub if I am trying to install dual boot to a system that already has WinXP on it? --> yes, recommend against grub-install

odeSolver · Posted: Sat Jul 17, 2010 6:09 pm Post subject:

DONAHUE · Posted: Sat Jul 17, 2010 6:12 pm Post subject:

HOSTNAME="jeffux" --> no problem

dns_domain_lo="jeffnet" --> scews up resolv.conf --> do not put in /etc/conf.d/net

Why recommend against using grub? --> use grub, but when setting up the MBR don't use grub-install command use grub command as shown.
so

odeSolver · Posted: Sat Jul 17, 2010 6:18 pm Post subject:

DONAHUE · Posted: Sat Jul 17, 2010 6:24 pm Post subject:

/etc/conf.d/net
# all comments (the file is essentially empty) --> good

/etc/conf.d/net --> TYPO?? --> good if in /etc/hosts --> not good if in /etc/conf.d/net
127.0.0.1 jeffux.jeffnet jeffux localhost
::1 localhost

Explanation: dns_domain_lo="jeffnet" will cause all info in /etc/resolv.conf to be overwritten by "search jeffnet "; this will cause a dns request to be routed to the dns server for the local domain jeffnet; as there is neither a local domain jeffnet nor a local dns server on it a lot of "could not find foo.com" messages will result.

BradN · Posted: Sat Jul 17, 2010 6:29 pm Post subject:

I assume you mean /etc/hosts for the last one, you can just omit jeffux.jeffnet entirely.

That file is formatted basically like:

(Return this IP address) (for this host name) (and this one) (and this...)

If you have a good router, other host names should be accessible automagically (being registered during dhcp), but if for some reason they don't work, you can add your other computers into the hosts file (but then you will want to assign them static IP's).

odeSolver · Posted: Sat Jul 17, 2010 6:45 pm Post subject:

I made the network changes you guys recommended. (Yes, that was a typo: last file was /etc/hosts).

BradN · Posted: Sat Jul 17, 2010 6:57 pm Post subject:

Your splashimage line should have (hd0,2) - remember grub's partition numbers are one less than linux reports - hda3 becomes (hd0,2).

You probably want real_root=/dev/hda3 but it's possible that the kernel will use new drivers that emulate SCSI - meaning your hard drive would be sda instead of hda - you'll know when you first try to boot into the system. If it does show up as sda, you'll have to also change /etc/fstab to reflect that.

You should be close to booting into gentoo now

DONAHUE · Posted: Sat Jul 17, 2010 7:01 pm Post subject:

But first, can I just use grub-install instead of the code you gave me? Does grub-install work with dual-boot systems? --> grub-install works well if you have 1 disk partitioned as hda1 boot, hda2 swap, hda3 root other than that I lack trust.

How come your grub.conf uses (hd0,0) for Linux, but uses 'root (hd0,2)' inside grub? I'm guessing that was just a typo. --> good catch. Some day I will read what I write.

Current grub.conf:

odeSolver · Posted: Sat Jul 17, 2010 7:40 pm Post subject:

BradN · Posted: Sat Jul 17, 2010 8:11 pm Post subject:

When you run the...
setup (hd0)
line, grub will install itself to the first sector of the hard drive (and use some empty space in the rest of the first 32KB to store the filesystem driver) and completely take over the boot sequence. The foolproof way to revert this to the way windows had it is by booting the windows install disc, going to the recovery console, and typing fixmbr (at least on XP). You could also back up your boot sector and restore it later.

To back up the boot sector (MBR) including partition table:
dd if=/dev/hda of=/mnt/gentoo/hda.mbr bs=512 count=1

To restore the boot sector and partition table:
dd if=/mnt/gentoo/hda.mbr of=/dev/hda bs=512 count=1

(to do this without restoring the partition table, change 512 to 448 - the partition table is the 64 bytes at the end of the sector. Take out /mnt/gentoo if you're doing this from within the chroot or within gentoo after it's installed)

Knoppix has a utility, "install-mbr" or something along those lines - don't use it because while the MBR it installs does work, it captures the F8 key to use for something else, and you can't get into the windows boot menu.

An alternative to all this is doing...
setup (hd0,2)
which will install grub only to your linux partition, in which case you will need to run fdisk and mark the linux partition as active with the windows partition inactive (window's MBR checks these active flags but grub doesn't). This can be easier to revert back than the first way. The only disadvantage is that you may have to reinstall grub after you update it, if grub's files are no longer in the same spot on disk. This is because when installed to the MBR, grub also puts its filesystem driver in the empty spot right after the MBR, but when installed to a partition there's no empty space for it, so it has to hardcode the location on disk of its filesystem driver into the tiny boot sector to load it.

An advantage of having a separate /boot partition is you can uninstall linux to reclaim the space but keep using grub to boot windows if you want to - most people wouldn't care but there are exotic configurations (mostly with >4 copies of windows or DOS, or booting secondary drives) that grub makes possible.

To sum all this up, my recommendation: Make a backup of your MBR just in case, and let grub install there because it'll probably be less hassle in the long run.

odeSolver · Posted: Sun Jul 18, 2010 1:03 am Post subject:

BradN · Posted: Sun Jul 18, 2010 3:57 am Post subject:

No problem, it's my way of giving back to the community for the great software I get.