Bug 430620
| Summary: | anaconda sets up wrong disk in grub | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 5 | Reporter: | Chris Pepper <pepper> |
| Component: | anaconda | Assignee: | Anaconda Maintenance Team <anaconda-maint-list> |
| Status: | CLOSED NOTABUG | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | low | ||
| Version: | 5.1 | CC: | hdegoede |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2009-11-30 11:06:22 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Chris Pepper
2008-01-29 04:56:44 UTC
Clarification -- the first problem is due to the way anaconda creates grub.conf (referring to hd0,0 when installing onto hd1,1). The second issue is because anaconda writes the MBR on the specified drive, but if that is not the default boot device this is not actually used. If anaconda is writing to a secondary (never used) MBR, it should warn the user that manual intervention will be required, either to use this MBR, or to configure the *active* MBR to boot to the RHEL being installed. With the "--driveorder=sdb" you are telling anaconda, that your BIOS boot order is first sdb, then sda. Grub harddisk numbers refer to BIOS harddisk numbers, so you are telling anaconda that: sdb == hd0 And therefor that: sda == hd1 And you are getting exactly the grub.conf that you ask for. Note that we also write a device.map to tell grub about: sdb == hd0 sda == hd1 So yes if you pass "--driveorder=sdb" the mbr will get written to the sdb disk, as you've told us that that is what the BIOS will boot from. Then is it impossible to create a configuration that can boot from sdb, with or without sda online? Sorry, I thought I was specifying a preference to boot from sdb, but now it sounds like perhaps I cannot have an sdb configured so it will work as a backup either way. (In reply to comment #3) > Then is it impossible to create a configuration that can boot from sdb, with or > without sda online? Sorry, I thought I was specifying a preference to boot from > sdb, but now it sounds like perhaps I cannot have an sdb configured so it will > work as a backup either way. The problem is in the: "with or without sda online?" Part of your wishes. To use sdb as a backup, when sda is "gone" what you did will work. As once sda is removed from the system sdb becomes the first bios drive (drive "80" in bios terms, hd0 in grub terms) and all is well. But when you are chainloading from sda's mbr sdb, is drive 81 / hd1, yet its grub is configured to look at hd0 -> fail. And if you configure its grub to look at hd1, then things will fail when sda is removed from the system, as now it is hd1. So for your purposes of having a backup installation ready to boot, what you did is correct, but to test this while sda is still in the system, you need to change the harddrive order in the BIOS (most modern BIOS's allow this). You cannot test this using chainloading. I hope this helps / clarifies, if not keep asking always happy to help. Regards, Hans \ |