Bug 1191305
| Summary: | Hot add disk to VM does not refresh "Installation Destination" screen | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Bryan Yount <byount> |
| Component: | anaconda | Assignee: | David Lehman <dlehman> |
| Status: | CLOSED ERRATA | QA Contact: | Release Test Team <release-test-team-automation> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 7.1 | CC: | glesage, mbanas, mkovarik, tgummels |
| Target Milestone: | rc | Keywords: | Reopened |
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | anaconda-21.48.22.75-1 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2016-11-03 23:06:58 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 1203710, 1295926, 1313485 | ||
| Attachments: | |||
Created attachment 990334 [details]
Hot add disk in RHEV
Created attachment 990335 [details]
After disk attached, nothing is automatically visible
Created attachment 990336 [details]
After clicking "Refresh" in the "Add disk" screen, a system disk is visible
Version-Release number of selected component (if applicable): anaconda-19.31.122-1.el7.x86_64.rpm Disks are scanned at startup, you need to use refresh to pick up any changes. Reopening. Then I believe we need to add a "Refresh" button to the main Disk page and not just under "Add disk". This is unintuitive for the user since they will hit refresh on that screen and see nothing appear until they go back one screen. I'm in agreement with Bryan, the UI is not intuitive for this use case. Also disconcerting is not seeing the added disk show up in the Add a disk screen after hitting Refresh List though I can see logically why it doesn't, the interface is intended for specialized and network devices not local. A customer would probably get pretty frustrated adding the disk to the VM, not seeing it appear automatically, deciding to hit the Add a disk, getting to the Add a disk screen then repeatedly hitting Refresh List because there is no indication anything has happened. It would be greatly appreciated if the UI could be modified to take in to account this use case. In most cases, it is a bad idea to have a refresh button... especially when the computer itself should know something has been changed. This especially holds true when one is trying to handle corner cases, such as in this bug report. (Aside: One very notable exception is when there's a high price to check concerning data and latency on something that most likely hasn't changed — prime example: a web page. But a web page is one of the very few exceptions.) Sometimes the best interface is no interface. The new local disk should appear when it is available. That's what's expected, and adding a widget to refresh (which is useless 99% of the time) isn't really the right approach. ## Solution 1: Polling How intensive is it to refresh local disks? It's probably more involved than checking /proc/partitions, certainly — but does it take any significant time or resources for Anaconda to check the status of locally available drives? Would it be possible to check the status of local disks every second or few while the "Installation Destination" view is active and refresh the "Local Standard Disks" part of UI if available disks change? ## Solution 2: udev Better yet: Using a udev rule to run a command when a disk is added (or removed) to tell Anaconda that disks have been refreshed. Something like one of the following lines in /etc/udev/rules.d/60-anaconda-disk-refresh.rules: ACTION=="add|remove", KERNEL=="sd[a-z]", RUN+="/usr/bin/something-to-tell-anaconda-the-disks-have-changed" SUBSYSTEM=="block", ACTION=="change", RUN+="/usr/bin/something-to-tell-anaconda-the-disks-have-changed" ...and it's possible to pass variables to the command or script too, so you can actually specify what exactly changed. Some pretty decent udev docs: http://reactivated.net/writing_udev_rules.html Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHEA-2016-2158.html |
Created attachment 990333 [details] Initial anaconda screen with no system disk present Description of problem: A system disk was hot added to a RHEL 7.1 VM in RHEV but the disk did not automatically show up on the "Installation Destination" screen. Version-Release number of selected component (if applicable): 7.1 beta How reproducible: 100% Steps to Reproduce: 1. Create a VM without a system disk 2. While the VM is running and waiting on the anaconda "Installation Destination" screen, hot add a disk to the system. Actual results: The disk does not automatically appear Expected results: The disk should appear without the user having to initiate a workaround Additional info: As a workaround, I got the disk to appear by clicking on the "Add disk" button and then selecting "Refresh" at the bottom right hand corner. Upon returning to the previous screen, the local disk was visible.