Once upon a time, Beniamino Galvani <bgalvani@xxxxxxxxxx> said:
> network-scripts do [1]:
>
> /sbin/arping -c 2 -w ${ARPING_WAIT:-3} -D -I ${REALDEVICE} ${ipaddr[$idx]}
>
> which waits 2 seconds by default.
Ahh, sorry, that's what I get for depending on memory. :)
> In the original RFC, the duration of the ACD process is between 4 and
> 7 seconds (depending on randomization), which is clearly too long on
> modern hardware.
Definitely agree.
> In the Fedora change proposal, the default ACD interval in NM is set
> to up to 3 seconds and is subject to the same randomization; in
> practice it would be between ~1.7 and 3 seconds. Perhaps that's still
> too much, and we can safely decrease it to e.g. 1 second max to reduce
> the activation delay.
Yeah, I think sending 2-3 requests separated by maybe 0.2 seconds, and
waiting another 0.2 seconds for a reply (so a total of 0.8 seconds) is
sufficient for modern networks. A number of DHCP servers do a ping
before issue as well (although there's no good way for a DHCP client to
tell), so it's just adding to the amount of time before the network
becomes usable.
DAD/ACD is a good thing, I'd just like to see the impact minimized. The
time taken at boot is not a big deal (as users have to log in and start
applications and such), but the time taken on resume from sleep is more
noticable (open the notebook lid, unlock, then... wait).
Thinking about servers... this would happen before network-online.target
is triggered, right? Any services that try to bind to configured IPs or
the like need to still work.
--
Chris Adams <linux@xxxxxxxxxxx>
--
_______________________________________________
devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx
Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx
Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
