Re: Squid and local multicast network

  I've been following this thread.
  We have a problem that when we use parents ,
  the delays become excessive. I've tried a
  multitude of configurations , and come tot the
  the conclusion because we so far away from
  nlanr.net , it is just not viable to parent
  because I suspect that packets are getting lost.
 
  The timeout is set to one second , and I find the
  only way to get a quick response is to simply
  turn off all the parents , and use them as siblings.
  
  Thats why I feel multicasting the solution. As I see
  it , one host is pinged , and one replies , and if that
  does not happen quick enough , the object is fetched directly.
  It seems that the more parents one has , the longer the delay is
  before a objects is delivered , and I'm worried about the time
  difference (Average of 500-600 Ms). Also , I'm reluctant to
  just set up a whole wack of siblings , it seems almost messy.
  
  I've experimented with parent rules , but it takes too much time
  to sit and tweak the whole day. I prefer the one ping , and the closest
  parent replies , or only one parent relies.
 
  Now , I've recompiled a kernel with multicast and Tunneling support
  and what I need to know is , how does one know that nlanr.mcast.ircache.net
  is 1.) Receiving 2.) Replying.
  Unfortanety I don't have the luxury of spending time sorting it out
  (Boss has a list off todos as long as my arm) , but a pointer as to what
  to look for would be appreciated.
  Squid 1.1.16 Linux Redhat4.2 Kernel 2.0.30 64 meg.

--Daniel Schroder
  Networld
  http://livewire.new.co.za (F) 419 3212
  mailto:daniel@new.co.za (T) 419 4430

On Thu, 28 Aug 1997, Duane Wessels wrote:

> srainey@rmplc.net writes:
>
> >I have 7 Squid caches running under BSDI 2.10 and all on the same IP
> >subnet. I wish to configure them as siblings and it seems reasonable to set
> >up a local multicast network. However, after a couple of hours surfing the
> >web I'm not much nearer being able to set this up.
> >
> >Multicast support is built into the kernel, but do I need to use mrouted if
> >I'm not routing traffic beyond my local subnet? Can I choose any address
> >from the 224.0.0.0/4 block given that I'm not routing this network, or is
> >there a block for private multicast networks (is that what 224.0.0.0/24 is
> >for)?
>
> You don't need mrouted if all machines are on the same subnet. Since
> mrouted is not running (and if mcast is not enabled in your routers)
> you should be able to use any address at all.
>
> >I've tried setting up rm-ps-squid-multicast.rmplc.co.uk to be 224.0.0.1 and
> >then using this in squid.conf (on the host rooster) ...
> >
> >mcast_groups 224.0.0.1
> >
> >cache_host rm-ps-squid-multicast.rmplc.co.uk multicast 8080 3130 ttl=64
> >cache_host adder.rmplc.co.uk sibling 8080 3130 multicast-responder
> >cache_host rattle.rmplc.co.uk sibling 8080 3130 multicast-responder
> >cache_host barracuda.rmplc.co.uk sibling 8080 3130 multicast-responder
> >cache_host elk.rmplc.co.uk sibling 8080 3130 multicast-responder
> >cache_host whale.rmplc.co.uk sibling 8080 3130 multicast-responder
> >cache_host eagle.rmplc.co.uk sibling 8080 3130 multicast-responder
>
>
> Hm, there might be something special about 224.0.0/24, but I'm not sure.
>
> Feel free to use local.mcast.ircache.net (224.0.14.33) if you can
> guarantee that your packets won't leave your net/org.
>
> >I've also added a route ....
> >
> >route add -net 224.0.0.0 -netmask 240.0.0.0 -interface 194.238.50.8
> >
> >where 194.238.50.8 is the IP address of the single ethernet port in the
> >server.
> >
> >I've also tried using 224.0.0.2 with no luck.
> >
> >If I ping 224.0.0.1 I get responses from all the other hosts, but Squid
> >just doesn't seem to be responding to multicast requests.
>
> tcpdump?
>
> Duane W.
>
Received on Fri Aug 29 1997 - 01:43:24 MDT