[Guix Info][7.1.5] Should warn user about losing Internet or DNS connection

Hi!

When downloading substitutes via wireless connection, several times I encountered a case where the host name of hydra cannot be resolved. So, the "guix system init" fails and suggests the use of "--fallback" option. However, rather than continuing with "guix system --fallback init", one should actually try "dhclient -v WIRELESS_INTERFACE_NAME" first and then do "guix system init" again instead of "guix system --fallback init". My installation process is now going well with this strategy. Previously, I kept using "--fallback" that didn't solve the problem due to network connectivity error because using "--fallback" brought up built errors.

--

Best regards,

Eus (FSF member #4445)

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Hi!

Eus <eus@member.fsf.org> skribis:

Are you installing GuixSD 0.10.0?

I would personally find it weird to warn about the possibility of losing

Internet connection. This is outside the scope of GuixSD, in a way.

WDYT?

However, in the past people reported that nscd, the name service cache

daemon, would sometimes fail without any good reason. If you think that

is the case, then this is definitely a bug that we should be

addressing.

Thanks,

Ludo’.

On Fri, Jul 15, 2016 at 11:10 PM, Ludovic Courtès <ludo@gnu.org> wrote:

Yes.

I would personally find it weird to warn about the possibility of losing

I suggest that to balance the suggestion of using "--fallback" option when

guix fails to download some substitutes.

So, what about if instead of warning in the installation doc, the guix

suggestion on using "--fallback" option also carries information on the

possibility of lost network connection?

However, in the past people reported that nscd, the name service cache

That is likely. How to debug nscd? Any option perhaps to make it more

verbose?

Thanks,

--

Best regards,

Eus

Eus <eus@member.fsf.org> skribis:

[...]

What makes you think so?

The problem we had in the past is that nscd would cache lookup failures

that happened when the Internet connection was missing, which made

subsequent lookups fail even though networking was back up:

http://bugs.gnu.org/22209

I believe this was fixed by commit

c96ba2cf5efc0ee5c10f0a49aeaa9a45a84de7ed.

It would be great if you could check whether the problem is

reproducible, even with a stable connection.

If it is indeed reproducible, then you could try running the

installation after turning nscd off with:

herd stop nscd

Thanks,

Ludo’.

Hello,

ludo@gnu.org (Ludovic Courtès) skribis:

Did you have a change to try and install 0.11.0? Do you still

experience these problems?

Thanks in advance,

Ludo’.

tags 23910 moreinfo

Hi Ludo!

Sorry for replying just now. I did not try to reproduce the bug back at

that time. So, I took the time yesterday to try to reproduce the bug. And,

I cannot reproduce the problem after repeating the following rough steps

two times with the same bootable disk and machine and network (but the

external connection to the ISP may have changed in the mean time):

1. Format my /dev/sda8

2. Swapon my /dev/sda7

3. mount my /dev/sda8 to /mnt

4. herd start cow-store /mnt

5. umount /tmp

6. mount --bind /mnt/tmp2 /tmp

7. ifconfig, wpa_supplicant, dhclient

8. guix pull

9. guix system --no-grub --keep-failed init /mnt/etc/config.scm /mnt

The whole process took just about 100 minutes.

So, I cannot reproduce the bug.

Thanks.

--

Best regards,

Eus (FSF member #4445)

In this digital era, where computing technology is pervasive, your freedom

depends on the software controlling those computing devices.

Join free software movement today! It is free as in freedom, not as in free

beer!

Join: http://www.fsf.org/jf?referrer=4445

On Fri, Sep 9, 2016 at 9:35 PM, Ludovic Courtès <ludo@gnu.org> wrote:

Hello!

Eus <eus@member.fsf.org> skribis:

Normally step #8 can be omitted because hydra.gnu.org still has binaries

for the packages 0.11.0 provides.

Step #6 is also redundant with step #4 (‘herd start cow-store’ make /tmp

a bind mount to /mnt/tmp; see gnu/system/install.scm:154.)

That’s a lot of time.

Great. Thanks for taking the time to verify!

Ludo’.

On Tue, Sep 13, 2016 at 4:52 PM, Ludovic Courtès <ludo@gnu.org> wrote:

Oh, I retried everything with 0.10.0 since I had the problem back then with

0.10.0.

I have not had the chance to try 0.11.0.

Thank you for letting me know this. That will save my time in the future.

Really? What is your approximate time?

Perhaps it is because I used 0.10.0, guix pull, and my Internet connection

here is slow.

Anytime!

--

Eus

Eus <eus@member.fsf.org> skribis:

[...]

Of course it’s a function of the Internet bandwidth, the configuration

you’re building, and the available binaries.

Hopefully installing 0.11.0 with the desktop kind of config, and with

relatively good Internet connection, takes less time. I haven’t tried

to measure though.

Thanks,

Ludo’.