{"id":136,"date":"2005-06-09T01:58:49","date_gmt":"2005-06-08T22:58:49","guid":{"rendered":"https:\/\/void.gr\/kargig\/blog\/?p=136"},"modified":"2005-06-09T02:04:31","modified_gmt":"2005-06-08T23:04:31","slug":"the-right-way-to-enable-udev-in-gentoo","status":"publish","type":"post","link":"https:\/\/www.void.gr\/kargig\/blog\/2005\/06\/09\/the-right-way-to-enable-udev-in-gentoo\/","title":{"rendered":"the right way to enable udev in gentoo"},"content":{"rendered":"

I know there are numerous postings and wiki articles on the net on how to enable udev on a linux distribution and specifically for Gentoo. Because I did not find anything complete here’s my version on doing all that. The were 2 reasons I started looking around for udev support, first reason was to have a special device for my olympus c70z so I did not have to “fdisk -l” every time I wanted to check on what device it was, and secondly to improve the usb_key+hotplug+xlockmore<\/a> stuff I had done earlier.<\/p>\n

BEWARE!!!
\nI am not writing this guide for complete newbies to linux and kernel stuff…I am not going to explain how to compile a kernel and where to put it and and and and…cause it would never end.<\/p>\n

First thing to do check your kernel settings!!<\/p>\n

Device Drivers -> USB Support
\n< *> Support for Host-side USB
\n[*] USB device filesystem
\n< *> EHCI HCD (USB 2.0) support
\n< *> OHCI HCD support<\/code><\/p>\n


\nFor SCSI support
\nDevice Drivers -> SCSI device support
\n[*] legacy \/proc\/scsi\/ support
\n< *> SCSI disk support
\n< *> SCSI generic support
\n<\/code>
\n
\nFor vfat file system support
\nFile systems -> DOS\/FAT\/NT Filesystems
\n< *> MSDOS fs support
\n< *> VFAT (Windows-95) fs support
\n<\/code><\/p>\n


\nRemove devfs support (If you want...<\/em>)
\nFile systems -> Pseudo filesystems
\n[ ] \/dev file system support (OBSOLETE)
\nBUT YOU MUST REMOVE !!!!<\/strong> below devfs support.
\n[ ] Automatically mount at boot (SAY NO TO THIS!!!!<\/strong>)
\n<\/code><\/p>\n

Then emerge the proper packages:
\nemerge -uDv udev hotplug baselayout<\/code><\/p>\n

Edit your \/etc\/conf.d\/rc<\/em>:
\nYou must<\/strong> have settings like that:
\nRC_DEVICES=\"udev\"
\nRC_DEVICE_TARBALL=\"yes\"
\nRC_DEVFSD_STARTUP=\"no\"
\n<\/code><\/p>\n

then:
\nsysctl -w kernel.hotplug=\"\/sbin\/udev\"
\nrc-update add hotplug boot<\/code><\/p>\n

In lilo.conf change the append line of your kernel adding this:
\nappend=\"gentoo=nodevfs\"<\/code>
\nand then type lilo to make the proper changes. <\/p>\n

If you rebooted now your system with the new kernel it should have been udev enabled.<\/p>\n

You might encounter mouse problems, because the old \/dev\/mouse symlink is lost with udev. Edit \/etc\/conf.d\/gpm and \/etc\/X11\/xorg.conf to replace \/dev\/mouse with \/dev\/input\/mouse0<\/p>\n

What’s next ? udev rules. You must make some rules for udev to properly find your devices.
\nI am going to explain how I wrote 3 simple rules for my digital camera, my usb stick and my usb-hdd.
\n1) DIGITAL CAMERA
\nWhen plugged in the usb port go check your dmesg. You should see something like:
\nAttached scsi removable disk sdb at scsi7, channel 0, id 0, lun 0
\nAttached scsi generic sg1<\/strong> at scsi7, channel 0, id 0, lun 0, type 0
\n<\/code><\/p>\n

now do this: udevinfo -a -p \/sys\/class\/scsi_generic\/sg1<\/strong>
\nand a bunch of info like that will appear in front of you:
\n looking at the device chain at '\/sys\/devices\/pci0000:00\/0000:00:10.0\/usb2\/2-2':
\n BUS=\"usb\"<\/strong>
\n ID=\"2-2\"
\n DRIVER=\"usb\"<\/em>
\n SYSFS{bConfigurationValue}=\"1\"
\n SYSFS{bDeviceClass}=\"00\"
\n SYSFS{bDeviceProtocol}=\"00\"
\n SYSFS{bDeviceSubClass}=\"00\"
\n SYSFS{bMaxPower}=\" 0mA\"
\n SYSFS{bNumConfigurations}=\"1\"
\n SYSFS{bNumInterfaces}=\" 1\"
\n SYSFS{bcdDevice}=\"0100\"
\n SYSFS{bmAttributes}=\"c0\"
\n SYSFS{detach_state}=\"0\"
\n SYSFS{devnum}=\"6\"
\n SYSFS{idProduct}=\"0109\"
\n SYSFS{idVendor}=\"07b4\"
\n SYSFS{manufacturer}=\"OLYMPUS\"<\/strong><\/em>
\n SYSFS{maxchild}=\"0\"
\n SYSFS{product}=\"C70Z,C7000Z\"
\n SYSFS{serial}=\"1234567890\"<\/strong><\/em>
\n SYSFS{speed}=\"12\"
\n SYSFS{version}=\" 2.00\"
\n<\/code>
\nWe just need the italic ones.
\nedit \/etc\/udev\/rules.d\/10-local.rules
\nand add something like this:
\nBUS=\"usb\", KERNEL=\"sd?1\", SYSFS{manufacturer}=\"OLYMPUS\", SYSFS{serial}=\"1234567890\", SYSFS{product}=\"C70Z,C7000Z\", NAME=\"%k\", SYMLINK=\"c70z\"<\/code><\/p>\n

YOUR VALUES WILL DEFER!!!<\/p>\n

now “mkdir -p \/mnt\/digicam” and add something like this in your \/etc\/fstab:
\n\/dev\/c70z \/mnt\/digicam vfat noatime,user,rw,sync,uid=1000 0 0<\/code><\/p>\n

mount \/mnt\/digicam and your camera is ready to extract the pictures from it!<\/p>\n

2) USB KEY
\nsame as above…but the rule and fstab entry will defer slightly:
\nudev rule:
\nBUS=\"usb\", SYSFS{serial}=\"23DE746790310A9B\", NAME=\"%k\", SYMLINK=\"mykey\"<\/code>
\nfstab entry:
\n\/dev\/mykey \/mnt\/usbkey vfat noatime,user,rw,sync,uid=1000 0 0<\/code><\/p>\n

3) USB HDD
\nudev rule:
\nBUS=\"scsi\", SYSFS{model}=\"00JB-32EVA0\", NAME{all_partitions}=\"wd-usb\" <\/strong><\/code>
\nfstab entry:
\n\/dev\/wd-usb1 \/mnt\/usbdisk ext3 noatime,users 0 0<\/code><\/p>\n

Remember my old post on pam_usb<\/a> ? It gets a lot better with udev!
\nedit \/etc\/pam.d\/login
\nand change the rule into something like this now:
\nauth sufficient \/lib\/security\/pam_usb.so proc_basename=\/proc\/scsi\/usb-storage\/1 !check_device force_device=\/dev\/mykey<\/em> allow_remote=1 fs=vfat debug=1 log_file=\/var\/log\/pam_usb.log
\n<\/code>
\nwhere \/dev\/mykey<\/em> is created by udev so it does not matter where the real device is…it will always symlink to mykey<\/em>!<\/p>\n

You can’t make it work ? Read these links…they might help you:
\nGentoo udev Guide<\/a>
\nGentoo Wiki – HOWTO_Install_a_digital_camera<\/a>
\nUDEV Primer<\/a>
\nUsing udev for Static Device Naming<\/a>
\nWriting UDEV rules<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

I know there are numerous postings and wiki articles on the net on how to enable udev on a linux distribution and specifically for Gentoo. Because I did not find anything complete here’s my version on doing all that. The were 2 reasons I started looking around for udev support, first reason was to have […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ep_exclude_from_search":false,"footnotes":""},"categories":[1,3],"tags":[],"class_list":["post-136","post","type-post","status-publish","format-standard","hentry","category-general","category-linux"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t