Set SRC PREF for routes when injecting routes to kernel
Hi all! Is it possible to set the SRC-Attribute on routes that will be inserted to kernel? I have private /31 networks to connect to other routers in my network and i don't want to see these private ip-addesses on a traceroute from a network with public ips. Every Router have a public IP-Address on his Loopback-Interface, so i can use that address for ICMP-Replies. Lets say 78.22.45.0/24 and 78.22.46.0/24 is my public network address space. router#1.lo = 78.22.46.1/32 router#1.eth1 = 10.0.0.1/31 ----- eBGP ----- router#2.eth1 = 10.0.0.2/31 router#2.eth2 = 78.22.45.1/24 router#1.lo = 78.22.46.2/32 On traceroutes i like to reply from a specific ip-address. In case of router#1 with 78.22.46.1 and for router#2 with 78.22.46.2 On Unix / Linux you can accomplish that feature with router#1# ip route add 78.22.45.0/24 via 10.0.0.2 src 78.22.46.1 So how can i set "src" with bird on import route filtering process?
Hi Michael, On Mon, Jan 15, 2018 at 08:49:24AM +0100, Michael Rack wrote:
Hi all!
Is it possible to set the SRC-Attribute on routes that will be inserted to kernel?
Yes, you can set krt_prefsrc = 78.22.46.2 for the prefixes you want. [ ... ] HTH, tim -- Tim Weippert http://weiti.org - weiti@weiti.org GPG Fingerprint - E704 7303 6FF0 8393 ADB1 398E 67F2 94AE 5995 7DD8
Hi, You can set krt_prefsrc when exporting to kernel in Linux. On Mon, Jan 15, 2018 at 8:49 AM, Michael Rack <mail@michaelrack.de> wrote:
Hi all!
Is it possible to set the SRC-Attribute on routes that will be inserted to kernel?
I have private /31 networks to connect to other routers in my network and i don't want to see these private ip-addesses on a traceroute from a network with public ips. Every Router have a public IP-Address on his Loopback-Interface, so i can use that address for ICMP-Replies.
Lets say 78.22.45.0/24 and 78.22.46.0/24 is my public network address space.
router#1.lo = 78.22.46.1/32 router#1.eth1 = 10.0.0.1/31 ----- eBGP ----- router#2.eth1 = 10.0.0.2/31 router#2.eth2 = 78.22.45.1/24 router#1.lo = 78.22.46.2/32
On traceroutes i like to reply from a specific ip-address. In case of router#1 with 78.22.46.1 and for router#2 with 78.22.46.2
On Unix / Linux you can accomplish that feature with router#1# ip route add 78.22.45.0/24 via 10.0.0.2 src 78.22.46.1
So how can i set "src" with bird on import route filtering process?
Perfect, that will do what i want. Thank you. But will it not be better to have that setting on an in-filter per route basis? On MIKROTIK BGP / OSPF you do that on a per route basis, so you can do some fancy things like "if routes learned from peer 1 set src to x.x.x.x, if learned from peer 2 set src to y.y.y.y". 2018-01-15 9:36 GMT+01:00 Alexander Zubkov <green@qrator.net>:
Hi,
You can set krt_prefsrc when exporting to kernel in Linux.
On Mon, Jan 15, 2018 at 8:49 AM, Michael Rack <mail@michaelrack.de> wrote:
Hi all!
Is it possible to set the SRC-Attribute on routes that will be inserted to kernel?
I have private /31 networks to connect to other routers in my network and i don't want to see these private ip-addesses on a traceroute from a network with public ips. Every Router have a public IP-Address on his Loopback-Interface, so i can use that address for ICMP-Replies.
Lets say 78.22.45.0/24 and 78.22.46.0/24 is my public network address space.
router#1.lo = 78.22.46.1/32 router#1.eth1 = 10.0.0.1/31 ----- eBGP ----- router#2.eth1 = 10.0.0.2/31 router#2.eth2 = 78.22.45.1/24 router#1.lo = 78.22.46.2/32
On traceroutes i like to reply from a specific ip-address. In case of router#1 with 78.22.46.1 and for router#2 with 78.22.46.2
On Unix / Linux you can accomplish that feature with router#1# ip route add 78.22.45.0/24 via 10.0.0.2 src 78.22.46.1
So how can i set "src" with bird on import route filtering process?
Uppps, okay sorry, that is a attribute on a per route / prefix basis as i want to. protocol bgp ibgp4_bgp02 {
description "Internal BGP to BGP02"; local 10.0.0.1 as 65501; neighbor 10.0.0.2 as 65502; ipv4 { export all; import filter { krt_prefsrc = 78.22.46.1; };
table ibgp4;
}; }
perfect, thank you. 2018-01-15 10:54 GMT+01:00 Michael Rack <mail@michaelrack.de>:
Perfect, that will do what i want. Thank you.
But will it not be better to have that setting on an in-filter per route basis?
On MIKROTIK BGP / OSPF you do that on a per route basis, so you can do some fancy things like "if routes learned from peer 1 set src to x.x.x.x, if learned from peer 2 set src to y.y.y.y".
2018-01-15 9:36 GMT+01:00 Alexander Zubkov <green@qrator.net>:
Hi,
You can set krt_prefsrc when exporting to kernel in Linux.
On Mon, Jan 15, 2018 at 8:49 AM, Michael Rack <mail@michaelrack.de> wrote:
Hi all!
Is it possible to set the SRC-Attribute on routes that will be inserted to kernel?
I have private /31 networks to connect to other routers in my network and i don't want to see these private ip-addesses on a traceroute from a network with public ips. Every Router have a public IP-Address on his Loopback-Interface, so i can use that address for ICMP-Replies.
Lets say 78.22.45.0/24 and 78.22.46.0/24 is my public network address space.
router#1.lo = 78.22.46.1/32 router#1.eth1 = 10.0.0.1/31 ----- eBGP ----- router#2.eth1 = 10.0.0.2/31 router#2.eth2 = 78.22.45.1/24 router#1.lo = 78.22.46.2/32
On traceroutes i like to reply from a specific ip-address. In case of router#1 with 78.22.46.1 and for router#2 with 78.22.46.2
On Unix / Linux you can accomplish that feature with router#1# ip route add 78.22.45.0/24 via 10.0.0.2 src 78.22.46.1
So how can i set "src" with bird on import route filtering process?
Hi everybody, I am wondering what is the state of krt_prefsrc or something similar that would work in FreeBSD? I was experimenting with this some time ago and I ended up having to do NAT on the inner address for the router to reach internet through specific address as the prefix that is set on our outer interface (BGP routing prefix) is not globally advertised. I am not a big expert on FreeBSD, so my question is, does the kernel support similar route attributes so that it can be added to bird? Now the documentation lists these options as Linux specific, and especially krt_prefsrc would come in handy also on non-linux systems. thanks, Olda On Mon, Jan 15, 2018 at 11:03 AM, Michael Rack <mail@michaelrack.de> wrote:
Uppps, okay sorry, that is a attribute on a per route / prefix basis as i want to.
protocol bgp ibgp4_bgp02 {
description "Internal BGP to BGP02"; local 10.0.0.1 as 65501; neighbor 10.0.0.2 as 65502; ipv4 { export all; import filter { krt_prefsrc = 78.22.46.1; };
table ibgp4;
}; }
perfect, thank you.
2018-01-15 10:54 GMT+01:00 Michael Rack <mail@michaelrack.de>:
Perfect, that will do what i want. Thank you.
But will it not be better to have that setting on an in-filter per route basis?
On MIKROTIK BGP / OSPF you do that on a per route basis, so you can do some fancy things like "if routes learned from peer 1 set src to x.x.x.x, if learned from peer 2 set src to y.y.y.y".
2018-01-15 9:36 GMT+01:00 Alexander Zubkov <green@qrator.net>:
Hi,
You can set krt_prefsrc when exporting to kernel in Linux.
On Mon, Jan 15, 2018 at 8:49 AM, Michael Rack <mail@michaelrack.de> wrote:
Hi all!
Is it possible to set the SRC-Attribute on routes that will be inserted to kernel?
I have private /31 networks to connect to other routers in my network and i don't want to see these private ip-addesses on a traceroute from a network with public ips. Every Router have a public IP-Address on his Loopback-Interface, so i can use that address for ICMP-Replies.
Lets say 78.22.45.0/24 and 78.22.46.0/24 is my public network address space.
router#1.lo = 78.22.46.1/32 router#1.eth1 = 10.0.0.1/31 ----- eBGP ----- router#2.eth1 = 10.0.0.2/31 router#2.eth2 = 78.22.45.1/24 router#1.lo = 78.22.46.2/32
On traceroutes i like to reply from a specific ip-address. In case of router#1 with 78.22.46.1 and for router#2 with 78.22.46.2
On Unix / Linux you can accomplish that feature with router#1# ip route add 78.22.45.0/24 via 10.0.0.2 src 78.22.46.1
So how can i set "src" with bird on import route filtering process?
On Mon, Jan 15, 2018 at 03:00:52PM +0100, Olda Plchot wrote:
Hi everybody, I am wondering what is the state of krt_prefsrc or something similar that would work in FreeBSD? I was experimenting with this some time ago and I ended up having to do NAT on the inner address for the router to reach internet through specific address as the prefix that is set on our outer interface (BGP routing prefix) is not globally advertised. I am not a big expert on FreeBSD, so my question is, does the kernel support similar route attributes so that it can be added to bird? Now the documentation lists these options as Linux specific, and especially krt_prefsrc would come in handy also on non-linux systems.
Hi It is not supported in BIRD, but i also don't know whether such route attributes are supported in FreeBSD kernel. Unfortunately this part of kernel API is rarely well-documented, and man 4 route does not show anything relevant. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."
participants (5)
-
Alexander Zubkov -
Michael Rack -
Olda Plchot -
Ondrej Zajicek -
Tim Weippert