From owner-freebsd-net@FreeBSD.ORG Thu Jul 16 16:50:03 2009 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 1272D106566B for ; Thu, 16 Jul 2009 16:50:03 +0000 (UTC) (envelope-from Brian.Jacobs@lodgenet.com) Received: from garbo.lodgenet.com (garbo.lodgenet.com [204.124.121.250]) by mx1.freebsd.org (Postfix) with ESMTP id C59E58FC21 for ; Thu, 16 Jul 2009 16:50:02 +0000 (UTC) (envelope-from Brian.Jacobs@lodgenet.com) Received: from hardy.lodgenet.com (hardy.lodgenet.com [10.16.101.109]) by garbo.lodgenet.com (8.12.11.20060308/8.12.11) with ESMTP id n6GGo1kR008123; Thu, 16 Jul 2009 11:50:01 -0500 Received: from sfcoex02.lodgenet.com (Not Verified[10.16.100.165]) by hardy.lodgenet.com with MailMarshal (v6, 4, 1, 5038) id ; Thu, 16 Jul 2009 11:50:01 -0500 Received: from host.lodgenet.com ([10.1.1.129]) by host.lodgenet.com with Microsoft SMTPSVC(6.0.3790.3959); Thu, 16 Jul 2009 11:50:00 -0500 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Date: Thu, 16 Jul 2009 12:50:00 -0400 Message-ID: <126E45722B459248997856ECB72DEB7701285DC2@host.lodgenet.com> In-Reply-To: <4A5F5927.3080904@elischer.org> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: GRE tunnel limitations Thread-Index: AcoGNNbm/PBfLtbTSturgrtD+n9ceQAACB1A References: <126E45722B459248997856ECB72DEB7701285DC0@host.lodgenet.com> <4A5F5927.3080904@elischer.org> From: "Jacobs, Brian" To: "Julian Elischer" X-OriginalArrivalTime: 16 Jul 2009 16:50:00.0948 (UTC) FILETIME=[75991340:01CA0635] Cc: freebsd-net@freebsd.org Subject: RE: GRE tunnel limitations X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 16 Jul 2009 16:50:03 -0000 IP unnumbered between the two boxen. I've built some scripts to automatically generate config files, and then other scripts to automagically create the GRE interfaces and inject appropriate routes. GRE numbers are assigned sequentially based on config file lines (and are of no consequence): gre45: flags=3D9051 metric 0 mtu 1476 tunnel inet 10.3.100.39 --> 207.230.84.130 inet 10.3.100.39 --> 10.11.146.129 netmask 0xffffffff=20 gre46: flags=3D9051 metric 0 mtu 1476 tunnel inet 10.3.100.39 --> 12.35.57.131 inet 10.3.100.39 --> 10.10.201.1 netmask 0xffffffff 10.3.100.39 is the primary Ethernet interface address of the local box (terminator). 10.10.201.1 is the inside Ethernet of the remote box. Routing statement for 10.0.0.0/8 live on the remote box, and individual routes live on the concentrator: root@yttrium /root# netstat -nr | grep 10.10.201 10.10.201.0/26 10.10.201.1 UGS 0 2042 gre46 10.10.201.1 10.3.100.39 UH 1 49263 gre46 /bmj -----Original Message----- From: Julian Elischer [mailto:julian@elischer.org]=20 Sent: Thursday, July 16, 2009 12:45 PM To: Jacobs, Brian Cc: freebsd-net@freebsd.org Subject: Re: GRE tunnel limitations Jacobs, Brian wrote: > Does anyone have some realistic data on the number of GRE/ipip tunnels > FreeBSD 7.x can reasonably terminate? Assume no IPsec, just standard > encapsulation. I have an ad-hoc need to terminate about 1,4000 static > GRE tunnels (as Cisco 7206's are backordered until September). J >=20 > =20 >=20 > Thanks in advance! >=20 > =20 >=20 > /bmj >=20 > _______________________________________________ > freebsd-net@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" The limitation would be that there is an interface for reach one and=20 the interface 'interface' uses a linked list. it might work but there=20 would probably be scaling issues. I've often thought that what we need is a way to do "bulk encapsulatin=20 interfaces" where there is not an "interface" assigned to each=20 destination. (at least not one that shows up in 'ifconfig'). How will you want to decide which gre interface to use for a given=20 packet? is it just a standard routing decision based on the remote=20 address?