Current-Users archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: long delay getting address from ISP w/-current dhcpcd

On Mon, 24 Jul 2017, Martin Husemann wrote:

> On Sun, Jul 23, 2017 at 10:20:50PM -0500, John D. Baker wrote:
> > Anyone else using a Soekris box with netbsd-8 or -current and 'dhcpcd'
> > for acquiring the public IP from their ISP?  Seeing long delays?
> Can you show the ifconfig output while it tries to acquire the address?

I was not able to capture it, but watching it, no IP was assigned for
about the first minute after starting 'dhcpcd'.  Then, it maintained an
IPv4LL address (at first TENTATIVE, later not so) until it was finally
able to obtain the routable address from the ISP about 45 minutes later.

I have a custom "dhcpcd.exit-hook" script that watches for address
changes and installs an alias address so the ADSL modem's local
configuration network (HTTP- and telnet-based status/config utilities)
is reachable.  The script also ensures that this alias truly is an
alias so the DHCP-acquired address remains the primary address for the
benefit of my 'pf' rule set.

In my early testing, I'd moved the "dhcpcd.exit-hook" aside.  When I
put it back, the only noticable change was a complaint from 'ifconfig'
that it couldn't assign requested address during network configuration
at boot time ("/etc/rc.d/network"), probably because there was no alias
to remove yet.  The alias address was then installed properly.

The interface remained in that state (IPv4LL primary address plus
RFC1918 alias address) until the routable address was finally acquired.

I suspect there is a time element involved.  During later testing, if
I reboot the router, it will resume its lease right away.  If the router
remains offline long enough, when it comes back up it will again take
a very long time to acquire a new lease.

If it means anything, the ISP's lease time is only 30 minutes (1800 sec).

|/"\ John D. Baker, KN5UKS               NetBSD     Darwin/MacOS X
|\ / jdbaker[snail]mylinuxisp[flyspeck]com    OpenBSD            FreeBSD
| X  No HTML/proprietary data in email.   BSD just sits there and works!
|/ \ GPGkeyID:  D703 4A7E 479F 63F8 D3F4  BD99 9572 8F23 E4AD 1645

Home | Main Index | Thread Index | Old Index