Does anyone know of a system service that will provide automatic IP failover on a system with dual (redudnant) Ethernet adapters? For example, I can simulate this by manually deactivating eth0 and activating eth1, although it takes about 15 secs for the MAC address to be updated. It should be relatively simple to write a program that monitors the current Ethernet interface and does the change-over automatically (and forces the MAC update), but before re-inventing the wheel, I suspect there is already a system program that already does this, I just haven''t found one on Red Hat 8.0. thanks in advance, --John Klingler _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
there are several; http://www.linux-ha.org/ is a good place to start. On Mon, 2003-09-29 at 10:36, John Klingler wrote:> Does anyone know of a system service that will provide automatic IP > failover on a system with dual (redudnant) Ethernet adapters? > > For example, I can simulate this by manually deactivating eth0 and > activating eth1, although it takes about 15 secs for the MAC address to > be updated. > > It should be relatively simple to write a program that monitors the > current Ethernet interface and does the change-over automatically (and > forces the MAC update), but before re-inventing the wheel, I suspect > there is already a system program that already does this, I just haven''t > found one on Red Hat 8.0. > > > thanks in advance, > > > --John Klingler > > > _______________________________________________ > LARTC mailing list / LARTC@mailman.ds9a.nl > http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/_______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
This would make greater sense/benefit/appropriateness on two different machines, I think. vrrpd is another good alternative. sourceforge is the repository. Regards Mohan -----Original Message----- From: lartc-admin@mailman.ds9a.nl [mailto:lartc-admin@mailman.ds9a.nl]On Behalf Of Ben Sent: Monday, September 29, 2003 11:12 PM To: lartc@mailman.ds9a.nl Subject: Re: [LARTC] IP Failover there are several; http://www.linux-ha.org/ is a good place to start. On Mon, 2003-09-29 at 10:36, John Klingler wrote:> Does anyone know of a system service that will provide automatic IP > failover on a system with dual (redudnant) Ethernet adapters? > > For example, I can simulate this by manually deactivating eth0 and > activating eth1, although it takes about 15 secs for the MAC address to > be updated. > > It should be relatively simple to write a program that monitors the > current Ethernet interface and does the change-over automatically (and > forces the MAC update), but before re-inventing the wheel, I suspect > there is already a system program that already does this, I just haven''t > found one on Red Hat 8.0. > > > thanks in advance, > > > --John Klingler > > > _______________________________________________ > LARTC mailing list / LARTC@mailman.ds9a.nl > http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/_______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/ _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
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S Mohan wrote:<br>
<blockquote type="cite"
cite="midMMEBKBBDEGGFLDBJHPGECEBOCJAA.smohan@vsnl.com">
<pre wrap="">This would make greater
sense/benefit/appropriateness on two different
machines, I think. vrrpd is another good alternative. sourceforge is the
repository.
</pre>
</blockquote>
vvrpd was designed just "to prove the concept" and is not recommended
in production environment.<br>
keepalived (<a class="moz-txt-link-freetext"
href="http://keepalived.sourceforge.net/">http://keepalived.sourceforge.net/</a>)
works great for me.<br>
<blockquote type="cite"
cite="midMMEBKBBDEGGFLDBJHPGECEBOCJAA.smohan@vsnl.com">
<pre wrap="">
Regards
Mohan
-----Original Message-----
From: <a class="moz-txt-link-abbreviated"
href="mailto:lartc-admin@mailman.ds9a.nl">lartc-admin@mailman.ds9a.nl</a>
[<a class="moz-txt-link-freetext"
href="mailto:lartc-admin@mailman.ds9a.nl">mailto:lartc-admin@mailman.ds9a.nl</a>]On
Behalf Of Ben
Sent: Monday, September 29, 2003 11:12 PM
To: <a class="moz-txt-link-abbreviated"
href="mailto:lartc@mailman.ds9a.nl">lartc@mailman.ds9a.nl</a>
Subject: Re: [LARTC] IP Failover
there are several; <a class="moz-txt-link-freetext"
href="http://www.linux-ha.org/">http://www.linux-ha.org/</a>
is a good place to start.
On Mon, 2003-09-29 at 10:36, John Klingler wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Does anyone know of a system service that will
provide automatic IP
failover on a system with dual (redudnant) Ethernet adapters?
For example, I can simulate this by manually deactivating eth0 and
activating eth1, although it takes about 15 secs for the MAC address to
be updated.
It should be relatively simple to write a program that monitors the
current Ethernet interface and does the change-over automatically (and
forces the MAC update), but before re-inventing the wheel, I suspect
there is already a system program that already does this, I just
haven''t
found one on Red Hat 8.0.
thanks in advance,
--John Klingler
_______________________________________________
LARTC mailing list / <a class="moz-txt-link-abbreviated"
href="mailto:LARTC@mailman.ds9a.nl">LARTC@mailman.ds9a.nl</a>
<a class="moz-txt-link-freetext"
href="http://mailman.ds9a.nl/mailman/listinfo/lartc">http://mailman.ds9a.nl/mailman/listinfo/lartc</a>
HOWTO: <a class="moz-txt-link-freetext"
href="http://lartc.org/">http://lartc.org/</a>
</pre>
</blockquote>
<pre wrap=""><!---->
_______________________________________________
LARTC mailing list / <a class="moz-txt-link-abbreviated"
href="mailto:LARTC@mailman.ds9a.nl">LARTC@mailman.ds9a.nl</a>
<a class="moz-txt-link-freetext"
href="http://mailman.ds9a.nl/mailman/listinfo/lartc">http://mailman.ds9a.nl/mailman/listinfo/lartc</a>
HOWTO: <a class="moz-txt-link-freetext"
href="http://lartc.org/">http://lartc.org/</a>
_______________________________________________
LARTC mailing list / <a class="moz-txt-link-abbreviated"
href="mailto:LARTC@mailman.ds9a.nl">LARTC@mailman.ds9a.nl</a>
<a class="moz-txt-link-freetext"
href="http://mailman.ds9a.nl/mailman/listinfo/lartc">http://mailman.ds9a.nl/mailman/listinfo/lartc</a>
HOWTO: <a class="moz-txt-link-freetext"
href="http://lartc.org/">http://lartc.org/</a>
</pre>
</blockquote>
<br>
<pre cols="72" class="moz-signature">--
Regards,
Andrew Kozachenko
Entri ltd.
_________________________________________________
/ \
| If you ever know the power of the dark side... |
\_________________________________________________/
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> This would make greater sense/benefit/appropriateness on two different > machines, I think. vrrpd is another good alternative. sourceforge is the > repository.In some cases, a filer for exemple, you just want to have two of it''s NICs connected to two different switches. Then you dont loose the filer when a switch burns or a cable is cut. Rgds, Ronnie. _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
On Tuesday, 30 September 2003, at 08:40:12 +0300, Andrew Kozachenko wrote:> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> >Ugh !. Please configure your mail client to send outgoing messages only in plain text, preferably wrapped at 75 characters or less. Thank you. -- Jose Luis Domingo Lopez Linux Registered User #189436 Debian Linux Sid (Linux 2.6.0-test5-mm3) _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
If anyone is interested, in my quest for a networking solution which
provides IP Failover on heterogenous redundant networks, I have listed
the solutions I found below. I would welcome comments from anyone who is
familiar with these.
1. faild - I have included a description below of a program daemon
which monitors the Ethernet connections and changes the routing
tables when a failure is detected. IP Failover is all this simple
program does. Being simple, however, makes it small and easy to port.
2. High Availability Linux Project (HAL) (http://linux-ha.org/) has
code available for FreeBsd and Solaris (and probably reasonably
portably to other UNIX platforms. It supports virtual (redundant)
servers but could probably therefore be configured to support
redundant LANs.
3. Advanced Network Services (ANS 2.3.x) for Linux* Operating
Systems. which is available from Intel on both PCs and UNIX
OS''s.
ANS provides IP Failover and much more, such as switch failover,
load leveling, etc. See:
http://www.intel.com/support/network/adapter/onlineguide/PRO1000/DOCS/SERVER/index.htm.
4. Linux Virtual Server Project (LVS) - VRRPD, Virtual Router
Redundancy Protocol (http://off.net/~jme/vrrpd/) which also
provides IP Failover. It implements RFC2338 but is only available
on Linux but may be portable. As with HAL, it is probably
configureable to provide redundant LAN.
It seems the days of industry-wide standards and interoperability are
becoming casualties of war.
John Klingler
Automatic IP Failover: faild
Figure 1 shows a typical redundant network configuration where all nodes
are connected to two, separate Ethernet LANs (here referred to as
Ethernet A and Ethernet B). Each node must have two Ethernet interfaces,
one for each LAN. Distinct IP addresses are assigned to all Ethernet
interfaces.
_____________________ . . .
| |
Host 1 Host 2
____|________ __|______ . . .
Figure 1: Typical Redundant Network Configuration
A route monitor daemon is started on all nodes. Each daemon is
configured to be either a responder or both a requestor and responder.
Typically the host daemons are requestor/responders.
Requestor daemons broadcast inquiry (INQ) packets on all available
networks at a specified interval. Upon receiving an INQ each responder
daemon sends back an acknowledgment (ACK) via the same route. These
packets are all sent using UDP (Unreliable Datagram Protocol) so the
daemons can quickly detect if a route is active.
If the requestor daemon does not get ACKs from a given node and if the
responder daemon does not get INQs as expected, then each daemon
independently determines that the particular route has become
unreliable, or more likely, has gone dead. Each daemon then changes its
local system routing tables so future traffic will be routed over the
alternate (and presumably healthy) LAN. This detection and failover
occurs very quickly, in a matter of a few seconds, depending on how the
daemon''s timing parameters are set.
When a route fails, network traffic carried by reliable protocols (such
as X Window traffic via TCP -- Transmission Control Protocol) is held in
abeyance until the IP stack recognizes that packets are not getting
through. When the IP stack times out packets waiting for delivery will
be retransmitted. Since the daemon has changed the routing tables the
retransmitted packets will go via the new route.
The IP time-out time is the critical parameter determining how long it
will take from initial route failure to establishing communication over
the new route. This parameter may or may not be user-settable on your
system. Field experience so far indicates lag times of 20-40 seconds
before communication resumes.
As soon as the original route becomes reliable again, the daemon will
restore the routing tables and communication resumes over the original
interface. There should be no noticeable delay on the switchback.
Request packet interval, failover interval, and switchback interval are
all configurable.
To initiate a failover daemon on your host system, use the following
convention:
faild [-r] [-t <n>] [-f <n>] [-s <n>] [-p <n>] [-l
<p>]
-r should launch requestor
-t <n> : timer interval (in secs) for sending of pkts
-f <n> : num missed pkts before if is invalidated
-s <n> : num good pkts before if is revalidated
-p <n> : port number to use -l <p> : full path to message log
file
* Note: This daemon currently runs on VxWorks, Digital UNIX and
Solaris, and is being ported to OpenVMS. Any other platforms would
require porting the daemon to the target OS.
On Tuesday 07 October 2003 21:55, John Klingler wrote:> If anyone is interested, in my quest for a networking solution which > provides IP Failover on heterogenous redundant networks, I have listed > the solutions I found below. I would welcome comments from anyone who is > familiar with these. > > 1. faild - I have included a description below of a program daemon > which monitors the Ethernet connections and changes the routing > tables when a failure is detected. IP Failover is all this simple > program does. Being simple, however, makes it small and easy to port. > 2. High Availability Linux Project (HAL) (http://linux-ha.org/) has > code available for FreeBsd and Solaris (and probably reasonably > portably to other UNIX platforms. It supports virtual (redundant) > servers but could probably therefore be configured to support > redundant LANs. > 3. Advanced Network Services (ANS 2.3.x) for Linux* Operating > Systems. which is available from Intel on both PCs and UNIX OS''s. > ANS provides IP Failover and much more, such as switch failover, > load leveling, etc. See: > > http://www.intel.com/support/network/adapter/onlineguide/PRO1000/DOCS/SERVE >R/index.htm. > > 4. Linux Virtual Server Project (LVS) - VRRPD, Virtual Router > Redundancy Protocol (http://off.net/~jme/vrrpd/) which also > provides IP Failover. It implements RFC2338 but is only available > on Linux but may be portable. As with HAL, it is probably > configureable to provide redundant LAN.If I was you, I should go for keepalived. This is part of LVS but you can also use it just for the ip Failover. Companies like IBM, RH, are using this so I think it can be trusted. http://freshmeat.net/projects/keepalived/ "In addition, it implements a VRRPv2 stack to handle director failover. " Stef -- stef.coene@docum.org "Using Linux as bandwidth manager" http://www.docum.org/ #lartc @ irc.openprojects.net _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/