Bug#774232: recommend using a wired connexion

[Antoine Beaupré]

Package: release-notes
Severity: normal

Section 4.1.5 goes through great lengths to prepare the operator with
a "safe" environment. However, there is no mention of networking per
se - shouldn't it be recommended that operators use a wired connexion
to do the upgrade, considering firmware often goes missing during
upgrades?

-- System Information:
Debian Release: 8.0
APT prefers testing
APT policy: (500, 'testing'), (1, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.16.0-4-amd64 (SMP w/2 CPU cores)
Locale: LANG=fr_CA.utf8, LC_CTYPE=fr_CA.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

[Antoine Beaupré]

Post by Antoine Beaupré
Package: release-notes
Severity: normal
Section 4.1.5 goes through great lengths to prepare the operator with
a "safe" environment. However, there is no mention of networking per
se - shouldn't it be recommended that operators use a wired connexion
to do the upgrade, considering firmware often goes missing during
upgrades?

Does it? Please explain.

Maybe I'm confusing the jessie upgrade with the wheezy one, but i was
under the impression that a major upgrade may drop some
license-encumbred firmare that may eventually disable the wifi card
during the upgrade...

a.
--
One of the things the Web teaches us is that everything is connected
(hyperlinks) and we all should work together (standards). Too often
school teaches us that everything is separate (many different
'subjects') and that we should all work alone.
- Aaron Swartz

[Andrei POPESCU]

Post by Antoine Beaupré
Maybe I'm confusing the jessie upgrade with the wheezy one, but i was
under the impression that a major upgrade may drop some
license-encumbred firmare that may eventually disable the wifi card
during the upgrade...

If a package is dropped from Debian's repositories it isn't removed from
the user's system unless some other package has a Conflicts or Breaks
against it, which wouldn't make much sense for a firmware package.

On the other hand for an upgrade done locally the network connection is
needed only during the package download phase. If the upgrade is remote
the issue wouldn't be restricted to wireless connections as some
ethernet chipsets also require firmware.

There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

Kind regards,
Andrei

[Antoine Beaupré]

Post by Andrei POPESCU

Post by Antoine Beaupré
Maybe I'm confusing the jessie upgrade with the wheezy one, but i was
under the impression that a major upgrade may drop some
license-encumbred firmare that may eventually disable the wifi card
during the upgrade...

If a package is dropped from Debian's repositories it isn't removed from
the user's system unless some other package has a Conflicts or Breaks
against it, which wouldn't make much sense for a firmware package.

Yeah, i didn't mean a package as much as a specific firmware within a
package.

Post by Andrei POPESCU
On the other hand for an upgrade done locally the network connection is
needed only during the package download phase. If the upgrade is remote
the issue wouldn't be restricted to wireless connections as some
ethernet chipsets also require firmware.
There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

That. Exactly. :) I would be terrified of doing a remote upgrade over
wifi, and that's probably because I know a little more what I am doing
than the average Debian user - so I think it makes sense to warn against
that particular foot-shooting device.

A.

[Andrei POPESCU]

Post by Antoine Beaupré

Post by Andrei POPESCU
If a package is dropped from Debian's repositories it isn't removed from
the user's system unless some other package has a Conflicts or Breaks
against it, which wouldn't make much sense for a firmware package.

Yeah, i didn't mean a package as much as a specific firmware within a
package.

... and I should have noticed your @debian.org address :(

A quick 'grep -i drop' over the changelogs of firmware-free and
firmware-nonfree doesn't reveal anything dangerous.

Kind regards,
Andrei

[Paul Gevers]

Hi,

On Mon, 05 Jan 2015 15:59:51 -0500 Antoine =?utf-8?Q?Beaupr=C3=A9?=

Post by Antoine Beaupré

Post by Andrei POPESCU
There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

That. Exactly. :) I would be terrified of doing a remote upgrade over
wifi, and that's probably because I know a little more what I am doing
than the average Debian user - so I think it makes sense to warn against
that particular foot-shooting device.

I expect this is still an issue, but I wonder how hypothetical this is.
Is there any evidence that this is a real issue? I would update remotely
over WiFi myself, but ...

So, if we want to share our worries, how to phrase this? Does the
following make sense?
"""
Upgrading systems remotely that are connected via WiFi managed by
Network Manager isn't recommended. Network Manager re-initializes the
connection on service restart which could lead to problems under certain
circumstances.
"""

Paul

[Antoine Beaupré]

Post by Paul Gevers
Hi,
On Mon, 05 Jan 2015 15:59:51 -0500 Antoine =?utf-8?Q?Beaupr=C3=A9?=

Post by Antoine Beaupré

Post by Andrei POPESCU
There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

That. Exactly. :) I would be terrified of doing a remote upgrade over
wifi, and that's probably because I know a little more what I am doing
than the average Debian user - so I think it makes sense to warn against
that particular foot-shooting device.

I expect this is still an issue, but I wonder how hypothetical this is.
Is there any evidence that this is a real issue? I would update remotely
over WiFi myself, but ...
So, if we want to share our worries, how to phrase this? Does the
following make sense?
"""
Upgrading systems remotely that are connected via WiFi managed by
Network Manager isn't recommended. Network Manager re-initializes the
connection on service restart which could lead to problems under certain
circumstances.
"""

The thing is am I do not believe the Debian package restarts network
manager automatically. I have needrestart here for stuff like that, and
even *that* blocks that automated restart by default...

a.

[Paul Gevers]

Hi Antoine,

Post by Antoine Beaupré

Post by Paul Gevers
On Mon, 05 Jan 2015 15:59:51 -0500 Antoine =?utf-8?Q?Beaupr=C3=A9?=

Post by Antoine Beaupré

Post by Andrei POPESCU
There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

That. Exactly. :) I would be terrified of doing a remote upgrade over
wifi, and that's probably because I know a little more what I am doing
than the average Debian user - so I think it makes sense to warn against
that particular foot-shooting device.

I expect this is still an issue, but I wonder how hypothetical this is.
Is there any evidence that this is a real issue? I would update remotely
over WiFi myself, but ...
So, if we want to share our worries, how to phrase this? Does the
following make sense?
"""
Upgrading systems remotely that are connected via WiFi managed by
Network Manager isn't recommended. Network Manager re-initializes the
connection on service restart which could lead to problems under certain
circumstances.
"""

The thing is am I do not believe the Debian package restarts network
manager automatically. I have needrestart here for stuff like that, and
even *that* blocks that automated restart by default...

So you changed you mind since you filed the bug? Or am I
misunderstanding you now?

Paul

[Paul Gevers]

Hi Antoine,

Post by Paul Gevers

Post by Antoine Beaupré
The thing is am I do not believe the Debian package restarts network
manager automatically. I have needrestart here for stuff like that, and
even *that* blocks that automated restart by default...

So you changed you mind since you filed the bug? Or am I
misunderstanding you now?

Could you please reply to my question? The buster release is drawing
nearer and I'd like to fix this issue in the release notes if needed
well before the release to give translators the change to get the
translations in place.

Paul

[Antoine Beaupré]

Post by Paul Gevers
Hi Antoine,

Post by Antoine Beaupré

Post by Paul Gevers
On Mon, 05 Jan 2015 15:59:51 -0500 Antoine =?utf-8?Q?Beaupr=C3=A9?=

Post by Antoine Beaupré

Post by Andrei POPESCU
There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

That. Exactly. :) I would be terrified of doing a remote upgrade over
wifi, and that's probably because I know a little more what I am doing
than the average Debian user - so I think it makes sense to warn against
that particular foot-shooting device.

I expect this is still an issue, but I wonder how hypothetical this is.
Is there any evidence that this is a real issue? I would update remotely
over WiFi myself, but ...
So, if we want to share our worries, how to phrase this? Does the
following make sense?
"""
Upgrading systems remotely that are connected via WiFi managed by
Network Manager isn't recommended. Network Manager re-initializes the
connection on service restart which could lead to problems under certain
circumstances.
"""

The thing is am I do not believe the Debian package restarts network
manager automatically. I have needrestart here for stuff like that, and
even *that* blocks that automated restart by default...

So you changed you mind since you filed the bug? Or am I
misunderstanding you now?

So I'm not sure anymore. It's been a *long* time now, and I am not sure
exactly why I filed that bug... I wish I had been more explicit on the
"why" back then and an actual failure mode I experienced. I'm pretty
sure there *was* something, but I can't trace it right now.

Now that we're working on bookworm, I think I agree that we should move
on.

I still think that people should use a wired connexion for upgrades, but
I am not feeling so strongly about this that it should be part of the
upgrade procedure. In fact, I believe I have myself done upgrades over
wifi without too much problems recently.

I don't actually buy the "wifi firmware goes away" theory anymore, and
if network manager restarts, who cares? You already have the packages
downloaded at this point and the worse that could happen there is that
you lose your network, which is something a reboot (which you need to do
anyways) would do as well.

So yeah, let's move on, and thanks for nursing all those bugs all those
years. :)

a.

[Hendrik Boom]

Post by Antoine Beaupré

Post by Paul Gevers
Hi Antoine,

Post by Antoine Beaupré

Post by Paul Gevers
On Mon, 05 Jan 2015 15:59:51 -0500 Antoine =?utf-8?Q?Beaupr=C3=A9?=

Post by Antoine Beaupré

Post by Andrei POPESCU
There might however be an issue with remote upgrades over wireless
connections handled by Network Manager as it still reinitializes the
connection on service restart, so doing a remote upgrade over wireless
could under specific circumstances lead to problems.

That. Exactly. :) I would be terrified of doing a remote upgrade over
wifi, and that's probably because I know a little more what I am doing
than the average Debian user - so I think it makes sense to warn against
that particular foot-shooting device.

I expect this is still an issue, but I wonder how hypothetical this is.
Is there any evidence that this is a real issue? I would update remotely
over WiFi myself, but ...
So, if we want to share our worries, how to phrase this? Does the
following make sense?
"""
Upgrading systems remotely that are connected via WiFi managed by
Network Manager isn't recommended. Network Manager re-initializes the
connection on service restart which could lead to problems under certain
circumstances.
"""

The thing is am I do not believe the Debian package restarts network
manager automatically. I have needrestart here for stuff like that, and
even *that* blocks that automated restart by default...

So you changed you mind since you filed the bug? Or am I
misunderstanding you now?

So I'm not sure anymore. It's been a *long* time now, and I am not sure
exactly why I filed that bug... I wish I had been more explicit on the
"why" back then and an actual failure mode I experienced. I'm pretty
sure there *was* something, but I can't trace it right now.
Now that we're working on bookworm, I think I agree that we should move
on.

I suspect the connection manager does get restarted on upgrade.

I'm on Devuan chimaera, so things may be different for me.

But whenever I do an upgrade, I start by overriding the entry in rexolv.conf that the connection manager put there ao that I get a regular DNS location (I usually choose 8.8.8.8 because I can remember it.)

(why do I do that? Because long long ago the connection manager seems to have memorized a particular one of Devuan's mirrors and now it always gives me that one and it happens to be broken). I will get it even if it is no longer i the list of Devuan mirrors..

But 8.8.8.8 gets me a new one, and that one works.

The entire upgrade than works cleanly, but afterward, if I look at resolv.conf, it has again been overwritten by the connection manager,

So I conclude that it has been restarted.

So I conclude that the upgrade does indeed restart the connection manager.

No problem on my laptop. But I imagine it could cause problems on a remote device it I were to lose contact.

-- hendrik

Post by Antoine Beaupré
I still think that people should use a wired connexion for upgrades, but
I am not feeling so strongly about this that it should be part of the
upgrade procedure. In fact, I believe I have myself done upgrades over
wifi without too much problems recently.
I don't actually buy the "wifi firmware goes away" theory anymore, and
if network manager restarts, who cares? You already have the packages
downloaded at this point and the worse that could happen there is that
you lose your network, which is something a reboot (which you need to do
anyways) would do as well.
So yeah, let's move on, and thanks for nursing all those bugs all those
years. :)
a.
--
La propriété est un piège: ce que nous croyons posséder nous possède.
- Alphonse Karr