Comment 40 for bug 2009141

------- Comment From <email address hidden> 2023-04-19 06:07 EDT-------
(In reply to comment #39)
> @Canonical, A general comment on usability for users. Recommend updating
> reference to "zdev" for users highlighting what type of "zdev" is expected ?
>
> A QETH network device (0e0f) and not a zfcp QDIO device [i.e.
> 0.0.100d,0.0.110d,0.0.120d,0.0.130d)

Regarding terminology: "zfcp QDIO" sounds odd to me as zfcp maintainer. Both qeth [the q stands for qdio] and zfcp are based on qdio.

I would like to avoid starting to specify exclusion lists as it's incomplete and would need to be maintained. Instead, let's just clearly specify the allowed list of zdev types.

Just as a reference, the list of zdev types that the backend tool knows (not necessarily all of which might be supported by subiquity as frontend):

https://www.ibm.com/docs/en/linux-on-systems?topic=sr-persistent-configuration
https://www.ibm.com/docs/en/linux-on-systems?topic=pc-view-configuration

# lszdev --list-types
TYPE DESCRIPTION
dasd FICON-attached Direct Access Storage Devices (DASDs)
dasd-eckd Enhanced Count Key Data (ECKD) DASDs
dasd-fba Fixed Block Architecture (FBA) DASDs
zfcp SCSI-over-Fibre Channel (FCP) devices and SCSI devices
zfcp-host FCP devices
zfcp-lun zfcp-attached SCSI devices
qeth OSA-Express and HiperSockets network devices
ctc Channel-To-Channel (CTC) and CTC-MPC network devices
lcs LAN-Channel-Station (LCS) network devices
generic-ccw Generic Channel-Command-Word (CCW) devices

>
> Even though a network device is implied, it is not clear to users what type
> of zdev is being asked for

@Canonical: I would like to understand if the user dialog really means to imply a network device. (looks like it just passed whatever the user entered to zdev from s390-tools and can thus configure any of the above zdev types; but it also appears during something that seems to imply a network device context)

>
> Reference to "zdev" is open to interpretation as to what type of z device is
> requested
> i.e. QETH network or zfcp QDIO device)
>
> One variation
> i.e.
> Attempt interactive netboot from a URL?
> yes no (default yes): yes

> Available qeth devices:
> 0.0.0db0 0.0.0dc0

Which zdev device types does subiquity support here and could it ever enumerate available (network) devices of another type than qeth, such as lcs or ctc?

If so, maybe a suitable terminology would be
"channel-attached network devices to activate (comma separated, optional):"
That would implicitly exclude PCIe-attached RoCE adapters, which don't need such preconfiguration, and it would also implicitly exclude zfcp and other channel-attached device types such as generic-ccw.

If not, then maybe just
"qeth network device to activate (comma separated, optional):"

> zdev to activate (comma separated, optional):
> 0.0.100d,0.0.110d,0.0.120d,0.0.130d <============ equals zfcp QDIO device
>
>
> Second variation
> Attempt interactive netboot from a URL?
> yes no (default yes):
> Available qeth devices:
> 0.0.0db0 0.0.0dc0 0.0.0e0f
> zdev to activate (comma separated, optional): 0e0f <============ equals QETH
> network device