On Thu, Jul 26, 2007 at 11:40:19AM +0200, Bastian Blank wrote: > Hi folks > > For the libata-pata support we need to change fstab on several arches to > not break all systems which uses them.
Not to mention bootloader configs and other things that may handle dump partitions. > We need to decide which arches needs this rewrite now and which value > should be filed in. And also, how should we re-write them? Should we just provide documentation, or also provide a utility to do it? linux-images w/ libata-pata should probably detect non-persistent names and fail to install, telling the user they need to run the upgrade utility (or manually upgrade) before continuing. > There are 5 or so variants: > - /dev/disk/by-id: Includes disk serial number or wwnn. > - /dev/disk/by-label: Filesystem label. Do all filesystems support labels? fat doesn't, iirc. > - /dev/disk/by-path: Includes pci device and lun. > - /dev/disk/by-uuid: UUID of filesystem. Maybe we want the uuid of md > devices also? Do all filesystems support UUID? > - LABEL= > - UUID= Another option is to leave the option to the user with a sane default. I'm thinking something like: 1) scan all config files we know about that contain such references 2) Probe these devices for available persistent-names 3) Present the list of available names to the user 4) re-write all config files that reference that device For 4), we could either try and incorporate all config file knowledge in the utility, or provide a hook system by which we make a name map available but each package is responsible for doing its own renaming. The latter would give us a pass on the "don't edit other package's config files" rule. > We have to support the following device types, I think: > - pata, sata, parallel scsi, sas > No problem, I would prefer by-id. It should be stable for this types > of devices. So a user needs to fix this entry for a disk replacement. > - fiberchannel > by-id. It includes the wwnn, which is defined as unique for each > device. If someone have more than one path to the disk, they need > multipath-tools anyway, which creates /dev/mapper/$wwnn. > - iscsi > This is a problem. iscsi have a stable identifier for a device, but it > is not exported by udev. udev provides the following: > | /dev/disk/by-id/scsi-16465616462656166333a3100000000000000000000000000 > This is the usual disc identification. And: > | > /dev/disk/by-path/ip-192.168.9.13:3260-iscsi-iqn.2007-07.org.zseries.debian00:storage.org.zseries.debian04v4-lun-1 > This includes the ip of the target, the id and the lun. The id is > defined to be unique for a device. > Maybe we want something like > > by-id/iscsi-iqn.2007-07.org.zseries.debian00:storage.org.zseries.debian04v4-lun-1. > More than one path needs multipath-tools also. > > The following devices can be ignored: > - md* > - mapper/* > - lvm symlinks > > Or should we ignore all devices which we don't know about? I would think so. -- dann frazier -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
