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<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff size=2>Sounds
like you should be able to do it with VLANs (Virtual LANs).</FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff
size=2>Solaris, you say?</FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff size=2>The
following section of the Solaris docs had a fairly good description of VLANs and
how they are configured:</FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff size=2><A
href="http://docs.sun.com/db/doc/816-4554/6maoq01n2?q=VLAN&a=view">http://docs.sun.com/db/doc/816-4554/6maoq01n2?q=VLAN&a=view</A></FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff size=2>For
Linux, a good place to start looking might be </FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff size=2><A
href="http://www.linuxjournal.com/article.php?sid=7268">http://www.linuxjournal.com/article.php?sid=7268</A></FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff
size=2>Regards,</FONT></SPAN></DIV>
<DIV><SPAN class=250112215-18082004><FONT face=Arial color=#0000ff
size=2>Uffe</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
owner-erlang-questions@erlang.org
[mailto:owner-erlang-questions@erlang.org]<B>On Behalf Of </B>Lennart
Öhman<BR><B>Sent:</B> den 18 augusti 2004 15:39<BR><B>To:</B>
erlang-questions@erlang.org<BR><B>Subject:</B> Clusters replying from same IP
address without a NAT?<BR><BR></FONT></DIV>
<DIV id=idOWAReplyText365 dir=ltr>
<DIV dir=ltr><FONT face="Courier New" color=#000000 size=2>A slightly off the
topic question...</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Anyone familiar with the
possibility to have a second "hidden"</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>IP </FONT><FONT
face="Courier New" size=2>address associated with a physical network interface
in</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Solaris style UNICIES. Hidden in
the sence that it does not</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>answer ARP questions, in order to
not confuse routers since I</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>plan to have several such hidden
interfaces on the same network</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>with the same IP
address.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>What is my problem?</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>I want to build a cluster of CPUs
running Erlang. Every CPU has</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>at least one own physical network
connection with a "world-wide"</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>known IP address. One CPU is
leader and receives UDP packets.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Other computers in the world
knows the IP address of the leader.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>The leader load balances by
relaying incoming messages using</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>distributed Erlang. The CPU "who"
gets the "job" eventually</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>replies to the original client.
The reply must look like it came</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>from the IP address of the
leader.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>I can not hide the cluster behind
a NAT since the individual CPUs</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>must be accessible too, by their
own IP addresses.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>/Lennart</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" color=#000000
size=2></FONT> </DIV></DIV>
<DIV id=idSignature13456 dir=ltr>
<DIV><FONT face="Courier New" color=#000000
size=2>-------------------------------------------------------------</FONT></DIV>
<DIV><FONT face="Courier New" color=#000000 size=2>Lennart
Ohman
phone : +46-8-587 623 27</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sjöland & Thyselius Telecom
AB cellular: +46-70-552 6735</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sehlstedtsgatan
6
fax : +46-8-667 8230</FONT></DIV>
<DIV><FONT face="Courier New" size=2>SE-115 28 STOCKHOLM,
SWEDEN email : <A
href="mailto:lennart.ohman@st.se">lennart.ohman@st.se</A></FONT></DIV></DIV></BLOCKQUOTE></BODY></HTML>