RE: gratuitous ARP with em interface.

From: Sreekanth (sreekanth_at_redlinenetworks.com)
Date: 05/30/03

  • Next message: Neelkanth Natu: "Re: ipfw rules vs routes to localhost?"
    To: <akanwar@digitarchy.com>, <freebsd-net@freebsd.org>
    Date: Thu, 29 May 2003 17:49:11 -0700
    
    

    I did a quick test just now and...
    Interestingly I did see GARP packets on the network with Em copper
    connected to a 100base Switch(I don't have a gigabit Copper switch
    rightnow).
    You might want to try these things.
    1) Ping immediately after the link comes up and see if it succeeds.(In
    1000baseTX switch).
    2) Connect it to a 100Base port and try.
    3) Connect to another machine with crossover cable and try

    First try 1 and if it fails try 2 and 3.

    Hope it helps.

    Sreekanth

    > -----Original Message-----
    > From: owner-freebsd-net@freebsd.org
    > [mailto:owner-freebsd-net@freebsd.org] On Behalf Of
    > akanwar@digitarchy.com
    > Sent: Thursday, May 29, 2003 4:54 PM
    > To: sreekanth@redlinenetworks.com; mvsjetti@hss.hns.com;
    > pete@he.iki.fi; ru@freebsd.org;
    > freebsdnic@mailbox.cps.intel.com; freebsd-net@freebsd.org;
    > akanwar@digitarchy.com
    > Subject: RE: gratuitous ARP with em interface.
    >
    >
    > Thanks all for you replies.
    >
    > > I haven't tried this, but I think the problem would go away if you
    > > changed WAIT_FOR_AUTO_NEG_DEFAULT to 0 in "if_em.h".
    >
    > Changed this. Did not work.
    >
    > > If u can do kernel debugging put break point at the
    > > "arp_ifinit" and verify if this was getting called or
    > > not.................. cheers, mahesh
    >
    > Will try this.
    >
    > > Could be attributed to the spanning tree in the switch.I have
    > > seen it happening(especially with cisco switches).I bet you
    > > are not able to send out any packet(Not just Garp).
    >
    > No. Spanning tree is turned off (Tried it with both IOS and
    > Catalyst switches).
    >
    > > I haven't looked that deep into why, but em is quite slow
    > > on coming up compared to fxp for example. Probably
    > something to do with
    > > hardware re-initialization.
    >
    > Correct, there is a delay. "ifconfig em0 inet x.x.x.x/y"
    > takes a few seconds to complete whereas "ifconfig fxp0 inet
    > x.x.x.x/y" returns instantly.
    >
    >
    > Is there a way to force gratituous arp ? ( Short of writing a
    > raw socket
    > utility)
    >
    > Thanks,
    > -ansh
    >
    > > > >On Wed, May 28, 2003 at 07:57:07PM -0400,
    > > > akanwar@digitarchy.com wrote:
    > > > >
    > > > >
    > > > >>Hi all,
    > > > >>
    > > > >>Is there a known issue with alias IPs on em interfaces not
    > > > sending out
    > > > >>gratuitous arps ?
    > > > >>
    > > > >>The situation is as follows:
    > > > >> I am running a custom redundancy daemon that migrates the
    > > > IP address
    > > > >>of a server from one interface to another in case the
    > > > active network
    > > > >>path fails. Till now I was experimenting with two fxp
    > > > interfaces and
    > > > >>everything worked perfectly. i.e. when the ip address moved over
    > > > >>(using a perl script to run ifconfig commands) it sent out
    > > > grat. arps
    > > > >>for each of its alias IPs. This allowed the router to
    > > > update its Arp
    > > > >>table and talk to the newly active interface.
    > > > >>
    > > > >>Now when I try running the code with em (gigabit Ethernet
    > > > over copper)
    > > > >>NICs, I simply do not see the gratuitous arps come out
    > of the new
    > > > >>interface.
    > > > >>
    > > > >>I am at a loss to understand what has changed. Could it
    > > be that the
    > > > >>line DOWN -> UP time of the em interface is longer thereby
    > > > causing a
    > > > >>loss of ARPs ? Any suggestions ?
    > > > >>
    > > > >>
    > > > >>
    > > > >Yes, I can reproduce this too, no gratuitous ARP is sent.
    > > > >
    > > > >
    > > > >Cheers,
    > > > >
    > > > >
    > > >
    > > >
    > > > _______________________________________________
    > > > freebsd-net@freebsd.org mailing list
    > > > http://lists.freebsd.org/mailman/listinfo/free> bsd-net To
    > > > unsubscribe, send any mail to
    > > > "freebsd-net-unsubscribe@freebsd.org"
    > > >
    > > > ---
    > > > Incoming mail is certified Virus Free.
    > > > Checked by AVG anti-virus system (http://www.grisoft.com).
    > > > Version: 6.0.483 / Virus Database: 279 - Release Date: 5/19/2003
    > > >
    > > >
    > >
    > > _______________________________________________
    > > freebsd-net@freebsd.org mailing list
    > > http://lists.freebsd.org/mailman/listinfo/free> bsd-net
    > > To
    > > unsubscribe, send any mail to
    > > "freebsd-net-unsubscribe@freebsd.org"
    > >
    > >
    > > ---
    > > Incoming mail is certified Virus Free.
    > > Checked by AVG anti-virus system (http://www.grisoft.com).
    > > Version: 6.0.483 / Virus Database: 279 - Release Date: 5/19/2003
    > >
    > >
    >
    >
    >
    > --------------------------------------------------------------------
    > mail2web - Check your email from the web at http://mail2web.com/ .
    >
    >
    > _______________________________________________
    > freebsd-net@freebsd.org mailing list
    > http://lists.freebsd.org/mailman/listinfo/free> bsd-net
    > To
    > unsubscribe, send any mail to
    > "freebsd-net-unsubscribe@freebsd.org"
    >
    > ---
    > Incoming mail is certified Virus Free.
    > Checked by AVG anti-virus system (http://www.grisoft.com).
    > Version: 6.0.483 / Virus Database: 279 - Release Date: 5/19/2003
    >
    >

    _______________________________________________
    freebsd-net@freebsd.org mailing list
    http://lists.freebsd.org/mailman/listinfo/freebsd-net
    To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org"


  • Next message: Neelkanth Natu: "Re: ipfw rules vs routes to localhost?"

    Relevant Pages

    • Re: Dell switch
      ... Copper is fine for the small setup. ... Nick ... "Eddie Allen" wrote: ... >> I am looking at purchasing the Dell powerconnect 3324 switch. ...
      (microsoft.public.backoffice.smallbiz2000)
    • Re: Phone Line Interfacing - FCC Part-68
      ... very expensive to take out equipment and bury it. ... I am not on a copper pair. ... switch to broadband, and the switch to fiber by Sprint. ... I have yet to see good performance from DSL, ...
      (sci.electronics.design)
    • Re: 100Mbps Ethernet Speed/Efficiency
      ... > It's an SBC, ... Copper trace PCI, but no plug-in connectors. ... mtu is actaully tuned on a per-interface basis. ... assuming your switch support jumbo frames. ...
      (Fedora)
    • Re: gigabit nic
      ... 10/100/100 copper. ... Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org ... To UNSUBSCRIBE, email to debian-user-REQUEST@xxxxxxxxxxxxxxxx ...
      (Debian-User)
    • alcian blue -phthalocyanine
      ... how you can switch the copper with an lanthanoid? ... thanx Carsten Klein ...
      (sci.chem)