ubuntu-installer makes a contradictional statement regarding layer2/layer3
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Ubuntu on IBM z Systems |
Fix Released
|
Wishlist
|
Unassigned | ||
debian-installer (Ubuntu) |
Fix Released
|
Wishlist
|
Dimitri John Ledkov |
Bug Description
== Comment: #0 - Thorsten Diehl <email address hidden> - 2016-02-03 12:05:19 ==
When I configure a qeth OSA device, the installer asks for device type, device and protocol layer:
Please choose the type of your primary network interface that you will need for
installing the Debian system (via NFS or HTTP). Only the listed devices are
supported.
Network device type:
1: ctc: Channel to Channel (CTC) or ESCON connection,
2: qeth: OSA-Express in QDIO mode / HiperSockets,
3: iucv: Inter-User Communication Vehicle - available for VM guests only,
4: virtio: KVM VirtIO,
Prompt: '?' for help> 2
2
Please select the OSA-Express QDIO / HiperSockets device.
Device:
1: 0.0.f5f0-
Prompt: '?' for help, default=1> 1
1
By default OSA-Express cards use layer3 mode. In that mode LLC headers are
removed from incoming IPv4 packets. Using the card in layer2 mode will make it
keep the MAC addresses of IPv4 packets.
Use this device in layer2 mode?
1: Yes [*] 2: No
Prompt: '?' for help, default=1>
The last question experienced a change according to https:/
Layer2 is the default, which is correct, since the qeth driver uses layer2 as default as well.
However, the introductional text says: "By default OSA-Express cards use layer3 mode."
And this is wrong and needs to be fixed. Correct wording is:
"By default OSA-Express cards use layer2 mode. In layer3 mode LLC headers are
removed from incoming IPv4 packets. Using the card in layer2 mode will make it
keep the MAC addresses of IPv4 packets."
== Comment: #2 - Thorsten Diehl <email address hidden> - 2016-02-03 12:08:52 ==
Although LP 1526801 deals with this subject, it is different.
LP 1526801 is implemented and closed. Now the documentational part in the installer needs to follow that. Thus I recommend to treat this as a separate bug.
tags: | added: architecture-s39064 bugnameltc-136517 severity-medium targetmilestone-inin1604 |
Changed in ubuntu: | |
assignee: | nobody → Skipper Bug Screeners (skipper-screen-team) |
affects: | ubuntu → debian-installer (Ubuntu) |
Changed in debian-installer (Ubuntu): | |
assignee: | Skipper Bug Screeners (skipper-screen-team) → Dimitri John Ledkov (xnox) |
Changed in ubuntu-z-systems: | |
status: | New → Triaged |
importance: | Undecided → Wishlist |
------- Comment From <email address hidden> 2016-02-04 02:52 EDT-------
HI,
(In reply to comment #0) 0.0.f5f1- 0.0.f5f2 [*], /bugs.launchpad .net/ubuntu/ +source/ s390-netdevice/ +bug/1526801
> When I configure a qeth OSA device, the installer asks for device type,
> device and protocol layer:
>
> Please choose the type of your primary network interface that you will need
> for
>
> installing the Debian system (via NFS or HTTP). Only the listed devices are
>
> supported.
> Network device type:
> 1: ctc: Channel to Channel (CTC) or ESCON connection,
> 2: qeth: OSA-Express in QDIO mode / HiperSockets,
> 3: iucv: Inter-User Communication Vehicle - available for VM guests only,
>
>
> 4: virtio: KVM VirtIO,
> Prompt: '?' for help> 2
> 2
>
> Please select the OSA-Express QDIO / HiperSockets device.
> Device:
> 1: 0.0.f5f0-
> Prompt: '?' for help, default=1> 1
> 1
>
> By default OSA-Express cards use layer3 mode. In that mode LLC headers are
> removed from incoming IPv4 packets. Using the card in layer2 mode will make
> it
> keep the MAC addresses of IPv4 packets.
> Use this device in layer2 mode?
> 1: Yes [*] 2: No
> Prompt: '?' for help, default=1>
>
> The last question experienced a change according to
> https:/
> Layer2 is the default, which is correct, since the qeth driver uses layer2
> as default as well.
>
I wonder why the default has been changed at all. The default is just a guess. The s390-netdevice does not have any heuristics to determine a potential correct default and I would have to investigate if that is possible.
The system administrator should provide information about whether layer2 or layer2 is used for a particular network interface. Statement like "By default OSA-Express cards" are incorrect as the modes can be configured. The same applies for HiperSocket devices. And also there is real and virtual OSA/HiperSockets.
One last note, if you misconfigure the layer2 setting you want get a network connection.