* Re: [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
@ 2004-03-24 6:05 ` RonSenykoff
2004-03-25 1:22 ` Lists @ Aptedtech
` (9 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: RonSenykoff @ 2004-03-24 6:05 UTC (permalink / raw)
To: lartc
This is a multipart message in MIME format.
--=_alternative 002179AF86256E61_Content-Type: text/plain; charset="US-ASCII"
<snip>
I have a private lan that is connected to the world via 3 dsl lines. I
put
up a linux box that handles all the dsl lines, lan gateway and all is
working well...until...one of the dsl lines goes down. My routing table
is:
x.x.x.x dev ppp0 proto kernel scope link src x.x.x.x
x.x.x.x dev ppp1 proto kernel scope link src x.x.x.x
x.x.x.x dev ppp2 proto kernel scope link src x.x.x.x
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.1
255.255.255.0/24 dev eth0 scope link
169.254.0.0/16 dev eth0 scope link
127.0.0.0/8 dev lo scope link
default equalize
nexthop via x.x.x.x dev ppp0 weight 1
nexthop via x.x.x.x dev ppp1 weight 1
nexthop via x.x.x.x dev ppp2 weight 1
When one of the dsl lines has trouble (temporarily looses sync, etc), the
kernel takes the entire default route out until the line comes back up.
When the line comes up, it puts a single default route back in instead of
the multipath route. If I can make it so the multipath route is
maintained
even when one of the dsl lines goes down, that would be great. Is there a
way to have just one of the hops removed from the default multipath while
the line is down and then reinserted back in as a hop in the multipath
route? Thanks for any input.
-Chris
</snip>
Do you have the stateful firewall settings in your script?
According to nano.txt
http://www.ssi.bg/~ja/nano.txt
"At least for netfilter (not sure for ipfwadm/ipchains), the firewall
must be stateful. This can be done by:
iptables -t filter -N keep_state
iptables -t filter -A keep_state -m state --state
RELATED,ESTABLISHED \
-j ACCEPT
iptables -t filter -A keep_state -j RETURN
iptables -t nat -N keep_state
iptables -t nat -A keep_state -m state --state
RELATED,ESTABLISHED \
-j ACCEPT
iptables -t nat -A keep_state -j RETURN
and calling this at the beginning of the script:
iptables -t nat -A PREROUTING -j keep_state
iptables -t nat -A POSTROUTING -j keep_state
iptables -t nat -A OUTPUT -j keep_state
iptables -t filter -A INPUT -j keep_state
iptables -t filter -A FORWARD -j keep_state
iptables -t filter -A OUTPUT -j keep_state
"
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<br><font size=1 face="Verdana"><i><snip></i></font>
<br><font size=1 face="Verdana"><i>I have a private lan that is connected
to the world via 3 dsl lines. I put<br>
up a linux box that handles all the dsl lines, lan gateway and all is<br>
working well...until...one of the dsl lines goes down. My routing
table is:<br>
<br>
x.x.x.x dev ppp0 proto kernel scope link src x.x.x.x<br>
x.x.x.x dev ppp1 proto kernel scope link src x.x.x.x<br>
x.x.x.x dev ppp2 proto kernel scope link src x.x.x.x<br>
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.1<br>
255.255.255.0/24 dev eth0 scope link<br>
169.254.0.0/16 dev eth0 scope link<br>
127.0.0.0/8 dev lo scope link<br>
default equalize<br>
nexthop via x.x.x.x dev ppp0 weight 1<br>
nexthop via x.x.x.x dev ppp1 weight 1<br>
nexthop via x.x.x.x dev ppp2 weight 1<br>
<br>
When one of the dsl lines has trouble (temporarily looses sync, etc), the<br>
kernel takes the entire default route out until the line comes back up.<br>
When the line comes up, it puts a single default route back in instead
of<br>
the multipath route. If I can make it so the multipath route is maintained<br>
even when one of the dsl lines goes down, that would be great. Is
there a<br>
way to have just one of the hops removed from the default multipath while<br>
the line is down and then reinserted back in as a hop in the multipath<br>
route? Thanks for any input.<br>
<br>
-Chris<br>
</snip></i></font>
<br>
<br><font size=1 face="Verdana">Do you have the stateful firewall settings
in your script?</font>
<br>
<br><font size=1 face="Verdana">According to nano.txt</font>
<br><font size=1 face="Verdana">http://www.ssi.bg/~ja/nano.txt</font>
<br>
<br><font size=1 face="Verdana">"At least for netfilter (not sure
for ipfwadm/ipchains), the firewall<br>
must be stateful. This can be done by:<br>
<br>
iptables -t filter -N keep_state<br>
iptables -t filter -A keep_state -m state --state RELATED,ESTABLISHED \<br>
-j
ACCEPT<br>
iptables -t filter -A keep_state -j RETURN<br>
<br>
iptables -t nat -N keep_state<br>
iptables -t nat -A keep_state -m state --state RELATED,ESTABLISHED \<br>
-j
ACCEPT<br>
iptables -t nat -A keep_state -j RETURN<br>
<br>
and calling this at the beginning of the script:<br>
<br>
iptables -t nat -A PREROUTING -j keep_state<br>
iptables -t nat -A POSTROUTING -j keep_state<br>
iptables -t nat -A OUTPUT -j keep_state<br>
iptables -t filter -A INPUT -j keep_state<br>
iptables -t filter -A FORWARD -j keep_state<br>
iptables -t filter -A OUTPUT -j keep_state<br>
"</font>
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^ permalink raw reply [flat|nested] 14+ messages in thread* RE: [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
2004-03-24 6:05 ` RonSenykoff
@ 2004-03-25 1:22 ` Lists @ Aptedtech
2005-10-26 21:47 ` comp.techs
` (8 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: Lists @ Aptedtech @ 2004-03-25 1:22 UTC (permalink / raw)
To: lartc
[-- Attachment #1: Type: text/plain, Size: 4088 bytes --]
<snip>
I have a private lan that is connected to the world via 3 dsl lines. I put
up a linux box that handles all the dsl lines, lan gateway and all is
working well...until...one of the dsl lines goes down. My routing table is:
x.x.x.x dev ppp0 proto kernel scope link src x.x.x.x
x.x.x.x dev ppp1 proto kernel scope link src x.x.x.x
x.x.x.x dev ppp2 proto kernel scope link src x.x.x.x
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.1
255.255.255.0/24 dev eth0 scope link
169.254.0.0/16 dev eth0 scope link
127.0.0.0/8 dev lo scope link
default equalize
nexthop via x.x.x.x dev ppp0 weight 1
nexthop via x.x.x.x dev ppp1 weight 1
nexthop via x.x.x.x dev ppp2 weight 1
When one of the dsl lines has trouble (temporarily looses sync, etc), the
kernel takes the entire default route out until the line comes back up.
When the line comes up, it puts a single default route back in instead of
the multipath route. If I can make it so the multipath route is maintained
even when one of the dsl lines goes down, that would be great. Is there a
way to have just one of the hops removed from the default multipath while
the line is down and then reinserted back in as a hop in the multipath
route? Thanks for any input.
-Chris
</snip>
Do you have the stateful firewall settings in your script?
According to nano.txt
http://www.ssi.bg/~ja/nano.txt
"At least for netfilter (not sure for ipfwadm/ipchains), the firewall
must be stateful. This can be done by:
iptables -t filter -N keep_state
iptables -t filter -A keep_state -m state --state
RELATED,ESTABLISHED \
-j ACCEPT
iptables -t filter -A keep_state -j RETURN
iptables -t nat -N keep_state
iptables -t nat -A keep_state -m state --state
RELATED,ESTABLISHED \
-j ACCEPT
iptables -t nat -A keep_state -j RETURN
and calling this at the beginning of the script:
iptables -t nat -A PREROUTING -j keep_state
iptables -t nat -A POSTROUTING -j keep_state
iptables -t nat -A OUTPUT -j keep_state
iptables -t filter -A INPUT -j keep_state
iptables -t filter -A FORWARD -j keep_state
iptables -t filter -A OUTPUT -j keep_state
"
/sbin/iptables-save
# Generated by iptables-save v1.2.7a on Wed Mar 24 15:54:00 2004
*nat
:PREROUTING ACCEPT [9983:812849]
:POSTROUTING ACCEPT [0:0]
:OUTPUT ACCEPT [3:174]
:keep_state - [0:0]
-A PREROUTING -j keep_state
-A POSTROUTING -o ppp+ -j MASQUERADE
-A POSTROUTING -j keep_state
-A OUTPUT -j keep_state
-A keep_state -m state --state RELATED,ESTABLISHED -j ACCEPT
-A keep_state -j RETURN
COMMIT
# Completed on Wed Mar 24 15:54:00 2004
# Generated by iptables-save v1.2.7a on Wed Mar 24 15:54:00 2004
*filter
:INPUT ACCEPT [1020:161876]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [425:33288]
:keep_state - [0:0]
-A INPUT -i lo -m state --state NEW,ESTABLISHED -j ACCEPT
-A INPUT -i ppp+ -m state --state INVALID -j DROP
-A INPUT -i ppp+ -m state --state ESTABLISHED -j ACCEPT
-A INPUT -i ppp+ -p tcp -j DROP
-A INPUT -i ppp+ -p udp -j DROP
-A INPUT -i ppp+ -p icmp -j DROP
-A INPUT -j keep_state
-A FORWARD -i ppp+ -o eth+ -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i eth+ -o ppp+ -j ACCEPT
-A FORWARD -j keep_state
-A OUTPUT -o lo -m state --state NEW,ESTABLISHED -j ACCEPT
-A OUTPUT -o ppp+ -m state --state NEW,ESTABLISHED -j ACCEPT
-A OUTPUT -j keep_state
-A keep_state -m state --state RELATED,ESTABLISHED -j ACCEPT
-A keep_state -j RETURN
COMMIT
# Completed on Wed Mar 24 15:54:00 2004
The link you reference (http://www.ssi.bg/~ja/nano.txt) suggests several
patches to be applied to the kernel for the routing described to be
possible. I would like to do this, but it is a company box and they want a
"standard" installation which basically means no patching for me. The box
is running the most up to date kernel for a RedHat 9.0 install. Thanks for
any input.
-Chris
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^ permalink raw reply [flat|nested] 14+ messages in thread* [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
2004-03-24 6:05 ` RonSenykoff
2004-03-25 1:22 ` Lists @ Aptedtech
@ 2005-10-26 21:47 ` comp.techs
2005-10-27 14:20 ` Edmundo Carmona
` (7 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: comp.techs @ 2005-10-26 21:47 UTC (permalink / raw)
To: lartc
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Hi, I am tring to us ip route to load balance between two interfaces.
ip route add equalize 10.200.1.0/24 nexthop via 10.200.0.2 dev neta nexthop via 10.200.0.2 dev neta2
Where neta and neta2 are gre tunnels. Testing show that packets travel in a single sided manner.
Do I need to use the multipath (IP_ROUTE_MULTIPATH_CACHED) module?
thx jason
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^ permalink raw reply [flat|nested] 14+ messages in thread* Re: [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (2 preceding siblings ...)
2005-10-26 21:47 ` comp.techs
@ 2005-10-27 14:20 ` Edmundo Carmona
2005-10-27 16:02 ` comp.techs
` (6 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: Edmundo Carmona @ 2005-10-27 14:20 UTC (permalink / raw)
To: lartc
Multipath takes a little more that just setting the default route. You
have to set separate routing tables for each interface involved in the
multipath routing (though I haven't understood yet why they are
needed.. the fact is that if you don't set them, multipath won't
route).
Also, even if you set it all right, it doesn't mean that if you send
two packets to a location X, one will go through one interface and the
second will go through the other. Routes are cached, and after a
routing decision has been made for the first packet, packets going to
that same host will go through the same interface till the caching
time has gone by.
On 10/26/05, comp.techs <comp.techs@aspenview.org> wrote:
> Hi, I am tring to us ip route to load balance between two interfaces.
>
>
>
> ip route add equalize 10.200.1.0/24 nexthop via 10.200.0.2 dev neta nexthop
> via 10.200.0.2 dev neta2
>
> Where neta and neta2 are gre tunnels. Testing show that packets travel in
> a single sided manner.
>
> Do I need to use the multipath (IP_ROUTE_MULTIPATH_CACHED) module?
>
> thx jason
> _______________________________________________
> LARTC mailing list
> LARTC@mailman.ds9a.nl
> http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
>
>
>
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
^ permalink raw reply [flat|nested] 14+ messages in thread* RE: [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (3 preceding siblings ...)
2005-10-27 14:20 ` Edmundo Carmona
@ 2005-10-27 16:02 ` comp.techs
2005-10-27 18:05 ` comp.techs
` (5 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: comp.techs @ 2005-10-27 16:02 UTC (permalink / raw)
To: lartc
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Hi, I also used TEQL this worked very well, but I require the (weight) option.
thx jason
________________________________
From: lartc-bounces@mailman.ds9a.nl on behalf of Edmundo Carmona
Sent: Thu 10/27/2005 8:20 AM
To: lartc
Subject: Re: [LARTC] multipath routing
Multipath takes a little more that just setting the default route. You
have to set separate routing tables for each interface involved in the
multipath routing (though I haven't understood yet why they are
needed.. the fact is that if you don't set them, multipath won't
route).
Also, even if you set it all right, it doesn't mean that if you send
two packets to a location X, one will go through one interface and the
second will go through the other. Routes are cached, and after a
routing decision has been made for the first packet, packets going to
that same host will go through the same interface till the caching
time has gone by.
On 10/26/05, comp.techs <comp.techs@aspenview.org> wrote:
> Hi, I am tring to us ip route to load balance between two interfaces.
>
>
>
> ip route add equalize 10.200.1.0/24 nexthop via 10.200.0.2 dev neta nexthop
> via 10.200.0.2 dev neta2
>
> Where neta and neta2 are gre tunnels. Testing show that packets travel in
> a single sided manner.
>
> Do I need to use the multipath (IP_ROUTE_MULTIPATH_CACHED) module?
>
> thx jason
> _______________________________________________
> LARTC mailing list
> LARTC@mailman.ds9a.nl
> http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
>
>
>
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
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^ permalink raw reply [flat|nested] 14+ messages in thread* RE: [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (4 preceding siblings ...)
2005-10-27 16:02 ` comp.techs
@ 2005-10-27 18:05 ` comp.techs
2005-11-17 20:47 ` comp.techs
` (4 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: comp.techs @ 2005-10-27 18:05 UTC (permalink / raw)
To: lartc
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Hi, using the following:
ip route add equalize 10.200.1.0/24 nexthop via 10.200.0.2 dev neta nexthop
> via 10.200.0.2 dev neta2
while doing a ->
while [ 1 ]
do
ip route flush cache
done
the transfer of packets almost seems equal?
thx jason
________________________________
From: lartc-bounces@mailman.ds9a.nl on behalf of comp.techs
Sent: Thu 10/27/2005 10:02 AM
To: Edmundo Carmona; lartc@mailman.ds9a.nl
Subject: RE: [LARTC] multipath routing
Hi, I also used TEQL this worked very well, but I require the (weight) option.
thx jason
________________________________
From: lartc-bounces@mailman.ds9a.nl on behalf of Edmundo Carmona
Sent: Thu 10/27/2005 8:20 AM
To: lartc
Subject: Re: [LARTC] multipath routing
Multipath takes a little more that just setting the default route. You
have to set separate routing tables for each interface involved in the
multipath routing (though I haven't understood yet why they are
needed.. the fact is that if you don't set them, multipath won't
route).
Also, even if you set it all right, it doesn't mean that if you send
two packets to a location X, one will go through one interface and the
second will go through the other. Routes are cached, and after a
routing decision has been made for the first packet, packets going to
that same host will go through the same interface till the caching
time has gone by.
On 10/26/05, comp.techs <comp.techs@aspenview.org> wrote:
> Hi, I am tring to us ip route to load balance between two interfaces.
>
>
>
> ip route add equalize 10.200.1.0/24 nexthop via 10.200.0.2 dev neta nexthop
> via 10.200.0.2 dev neta2
>
> Where neta and neta2 are gre tunnels. Testing show that packets travel in
> a single sided manner.
>
> Do I need to use the multipath (IP_ROUTE_MULTIPATH_CACHED) module?
>
> thx jason
> _______________________________________________
> LARTC mailing list
> LARTC@mailman.ds9a.nl
> http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
>
>
>
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
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^ permalink raw reply [flat|nested] 14+ messages in thread* [LARTC] multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (5 preceding siblings ...)
2005-10-27 18:05 ` comp.techs
@ 2005-11-17 20:47 ` comp.techs
2007-06-05 9:13 ` [LARTC] Multipath routing Michał Margula
` (3 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: comp.techs @ 2005-11-17 20:47 UTC (permalink / raw)
To: lartc
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Hi, I have set up multipath routing using two gre tunnels. The multipath routes are setup via (zebra/ospf).
I managed to modify zebra not to include the 'equalize' in the multpath route, and set the weights 1:2.
My question is that after doing 4+ ftp transfers I still do not see much traffic on the interface with a weight of 1 even thought the first tunnel is near maximum capacity. If this is due to the route cache, is there a way to reduce
the TTL on the cache ?
thx jason
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^ permalink raw reply [flat|nested] 14+ messages in thread* [LARTC] Multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (6 preceding siblings ...)
2005-11-17 20:47 ` comp.techs
@ 2007-06-05 9:13 ` Michał Margula
2007-06-05 19:46 ` Piotr Chytla
` (2 subsequent siblings)
10 siblings, 0 replies; 14+ messages in thread
From: Michał Margula @ 2007-06-05 9:13 UTC (permalink / raw)
To: lartc
Hello!
I have trouble with multipath routing. Those options are enabled in kernel:
[*] IP: policy routing
[*] IP: equal cost multipath
[*] IP: equal cost multipath with caching support (EXPERIMENTAL)
<*> MULTIPATH: round robin algorithm
But issuing:
ip r a 1.2.3.0/23 scope global equalize nexthop via 80.245.176.11 \
dev eth0 weight 1 nexthop via 80.245.176.13 dev eth0 weight 1
and then
# ip r s
[...]
1.2.3.0/24
nexthop via 80.245.176.11 dev eth0 weight 1
nexthop via 80.245.176.13 dev eth0 weight 1
As you can see there is no equalize keyword in here.
Also I have trouble using multipath quagga, it simply doesn't put
multipath route in routing table.
For example:
faramir# sh ip bgp 10.100.0.1
BGP routing table entry for 10.101.0.0/22
Paths: (2 available, best #1, table Default-IP-Routing-Table)
Not advertised to any peer
Local
80.245.176.13 (metric 1) from 80.245.176.13 (80.245.177.4)
Origin IGP, metric 0, localpref 100, weight 150, valid, internal,
best
Last update: Tue Jun 5 01:59:29 2007
Local
80.245.176.10 (metric 1) from 80.245.176.10 (80.245.176.10)
Origin IGP, metric 0, localpref 100, weight 100, valid, internal
Last update: Tue Jun 5 01:28:02 2007
# ip r s
[...]
10.100.0.0/22 via 80.245.176.11 dev eth0 proto zebra
But if I manually put something like that in quagga:
faramir(config)# ip route 1.2.3.0/24 80.245.176.13
faramir(config)# ip route 1.2.3.0/24 80.245.176.11
Then:
# ip r s
[...]
1.2.3.0/24
nexthop via 80.245.176.11 dev eth0 weight 1
nexthop via 80.245.176.13 dev eth0 weight 1
Please help, I am out of ideas.
--
Micha³ Margula, alchemyx@uznam.net.pl, http://alchemyx.uznam.net.pl/
"W ¿yciu piêkne s± tylko chwile" [Ryszard Riedel]
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^ permalink raw reply [flat|nested] 14+ messages in thread* Re: [LARTC] Multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (7 preceding siblings ...)
2007-06-05 9:13 ` [LARTC] Multipath routing Michał Margula
@ 2007-06-05 19:46 ` Piotr Chytla
2007-06-06 10:05 ` Michał Margula
2007-06-07 9:07 ` Michał Margula
10 siblings, 0 replies; 14+ messages in thread
From: Piotr Chytla @ 2007-06-05 19:46 UTC (permalink / raw)
To: lartc
On Tue, Jun 05, 2007 at 11:13:52AM +0200, Micha³ Margula wrote:
> Hello!
>
Hi
> I have trouble with multipath routing. Those options are enabled in
> kernel:
>
> [*] IP: policy routing
> [*] IP: equal cost multipath
> [*] IP: equal cost multipath with caching support (EXPERIMENTAL)
> <*> MULTIPATH: round robin algorithm
>
First of all equal cost multipathing is evil ;>, It simply doesn't work for packets in
forwarding path besides support in kernel is not maintained
Realy if you want load balance both uplinks disable
CONFIG_IP_ROUTE_MULTIPATH_CACHED and you will have random traffic
distribiution between both links.
More details :
http://lists.openwall.net/netdev/2007/03/14/50
http://lists.openwall.net/netdev/2007/03/12/76
http://lists.quagga.net/pipermail/quagga-users/2007-May/008469.html
> Also I have trouble using multipath quagga, it simply doesn't put
> multipath route in routing table.
>
> For example:
>
> faramir# sh ip bgp 10.100.0.1
> BGP routing table entry for 10.101.0.0/22
> Paths: (2 available, best #1, table Default-IP-Routing-Table)
> Not advertised to any peer
> Local
> 80.245.176.13 (metric 1) from 80.245.176.13 (80.245.177.4)
> Origin IGP, metric 0, localpref 100, weight 150, valid, internal,
> best
> Last update: Tue Jun 5 01:59:29 2007
>
> Local
> 80.245.176.10 (metric 1) from 80.245.176.10 (80.245.176.10)
> Origin IGP, metric 0, localpref 100, weight 100, valid, internal
> Last update: Tue Jun 5 01:28:02 2007
>
BGP always have alternative paths in BGP RIB and mostly don't insert them
as multipath route to FIB.
Of course there is path : http://lebon.org.ua/quagga.html that force
route to be inserted to kernel with multiple gateways - but realy this
is some kind of dirty-hack.
Check thread 'Linux and BGP multipath' on quagga-dev, and especially this mail:
http://lists.quagga.net/pipermail/quagga-dev/2007-April/004700.html
> # ip r s
> [...]
> 10.100.0.0/22 via 80.245.176.11 dev eth0 proto zebra
>
> But if I manually put something like that in quagga:
>
> faramir(config)# ip route 1.2.3.0/24 80.245.176.13
> faramir(config)# ip route 1.2.3.0/24 80.245.176.11
>
yeah this is static route.
/pch
--
Dyslexia bug unpatched since 1977 ...
exploit has been leaked to the underground.
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^ permalink raw reply [flat|nested] 14+ messages in thread* Re: [LARTC] Multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (8 preceding siblings ...)
2007-06-05 19:46 ` Piotr Chytla
@ 2007-06-06 10:05 ` Michał Margula
2007-06-07 9:07 ` Michał Margula
10 siblings, 0 replies; 14+ messages in thread
From: Michał Margula @ 2007-06-06 10:05 UTC (permalink / raw)
To: lartc
Piotr Chytla pisze:
> First of all equal cost multipathing is evil ;>, It simply doesn't work for packets in
> forwarding path besides support in kernel is not maintained
>
> Realy if you want load balance both uplinks disable
> CONFIG_IP_ROUTE_MULTIPATH_CACHED and you will have random traffic
> distribiution between both links.
>
> More details :
> http://lists.openwall.net/netdev/2007/03/14/50
> http://lists.openwall.net/netdev/2007/03/12/76
> http://lists.quagga.net/pipermail/quagga-users/2007-May/008469.html
>
Oh. I see. Thanks. BTW: google doesn't show that links when looking for
multipath on linux :-)
Random load sharing over multiple routes is not a good idea, or maybe is
it? Am I guessing right that with enough amount of traffic and having
two nexthops it will split 50%/50% ?
> BGP always have alternative paths in BGP RIB and mostly don't insert them
> as multipath route to FIB.
>
> Of course there is path : http://lebon.org.ua/quagga.html that force
> route to be inserted to kernel with multiple gateways - but realy this
> is some kind of dirty-hack.
I know that site, but I thought that those patches were obsoleted,
because of --multipath option when compiling quagga.
> Check thread 'Linux and BGP multipath' on quagga-dev, and especially this mail:
>
> http://lists.quagga.net/pipermail/quagga-dev/2007-April/004700.html
I know that also :). BTW: until now I was quite pleased with linux
networking which quality is amazing. But now, when I need loadbalancing
I am disapointed, because it doesn't support things that with cisco
hardware you take for granted. I miss mostly recursive routes.
Something like that
ip route add 80.245.177.4/32 via 80.245.176.11
ip route add 10.0.0.0/24 via 80.245.177.4
It would solve problems with multipath bgp and loadbalancing because I
could add remove additional routes to 80.245.177.4 (or some other
imaginary loopback) and it would work as expected.
I hope it will be added some day :)
Thank you for your help!
--
Micha³ Margula, alchemyx@uznam.net.pl, http://alchemyx.uznam.net.pl/
"W ¿yciu piêkne s± tylko chwile" [Ryszard Riedel]
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^ permalink raw reply [flat|nested] 14+ messages in thread* Re: [LARTC] Multipath routing
2004-03-24 2:18 [LARTC] multipath routing Lists @ Aptedtech
` (9 preceding siblings ...)
2007-06-06 10:05 ` Michał Margula
@ 2007-06-07 9:07 ` Michał Margula
10 siblings, 0 replies; 14+ messages in thread
From: Michał Margula @ 2007-06-07 9:07 UTC (permalink / raw)
To: lartc
Piotr Chytla pisze:
> First of all equal cost multipathing is evil ;>, It simply doesn't work for packets in
> forwarding path besides support in kernel is not maintained
>
> Realy if you want load balance both uplinks disable
> CONFIG_IP_ROUTE_MULTIPATH_CACHED and you will have random traffic
> distribiution between both links.
>
Unfortunately it still doesn't work as expected. When i ping some host
it always go trough one nexthop. It does per-destination loadbalancing,
I am afraid.
--
Micha³ Margula, alchemyx@uznam.net.pl, http://alchemyx.uznam.net.pl/
"W ¿yciu piêkne s± tylko chwile" [Ryszard Riedel]
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^ permalink raw reply [flat|nested] 14+ messages in thread