Unless you set an obscenely short DNS xxxx-timeout interval, then your site would be down for up to the duraton of the timeout interval if one of your links failed. This really isn't an option for a mission critical op. If this was the way you wanted to go, it would be better to get two links (through 2 different physical media..I.e. T-1 and DSL) to an ISP with a 99.999% SLA, and use them as your exclusive ISP. Thoughts, Ejay ----Original Message Follows---- From: "Adrian Chew" <[EMAIL PROTECTED]> Reply-To: "Adrian Chew" <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: BGP, Multihoming, and Me Date: Fri, 13 Oct 2000 12:26:07 -0400 John, There might be ways to get this done other than BGP... http://www.cisco.com/warp/public/cc/pd/iosw/ioft/ionetn/tech/emios_wp.htm Take a look at the multi-homing with NAT. I do see some possible problems - with DNS and how your hosts are resolved. You could have a server hosted elsewhere which points/re-directs traffic via either ISP via the 2 different links depending on which one is available or load-balance between the 2. Regards, Adrian "John Neiberger" <[EMAIL PROTECTED]> wrote in message 31767142.971447738012.JavaMail.imail@tiptoe">news:31767142.971447738012.JavaMail.imail@tiptoe... > I have a question that I'm sure has been referenced before but I couldn't > find an answer in the archives, and it's more practical than technical. > > We have a single T-1 connection to an ISP for customer access to our > internal webservers so that our banking customers can do web-based > transactions and get account information. This is such an important aspect > of our business that we decided to get a second T-1 to another ISP for > redundancy. We aren't as concerned with being able to load-balance, which > is a dicey prospect in this arrangement anyway. > > Now, the problem: we have a tiny subnet assigned to us from ISP-1, it's a > /27. Now let's say we get a connection to ISP-2 and we start running BGP. > Is ISP-2 probably going to have a problem letting us advertise such a small > set of routes? I've been hearing that big ISPs tend not to want to > advertise subnets smaller than a /18. If that's the case, our plan is in > trouble. > > Now, problem #2: even if we can advertise a /27 through ISP-2, ISP-1 is > going to have to agree to advertise our /27 along with their aggregate > advertisement. If they don't, and they only advertise their aggregate, this > will cause return traffic to our network to come through ISP-2 because it > will be advertising a more specific route, correct? If that's correct, do > ISPs tend to have a problem with this arrangement? > > Basically, are we setting ourselves up for disappointment? Are there any > other factors that I should be aware of that I'm not considering? Should I > become a yak herder and move to Nepal? > > Thanks, as usual... > John Neiberger > > > > > > _______________________________________________________ > Say Bye to Slow Internet! > http://www.home.com/xinbox/signup.html > > _________________________________ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _________________________________ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com. _________________________________ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
