RE: [load balancing] Alteon - Client Web Proxy Problems

From: Pete Tenereillo (
Date: Thu Jul 15 2004 - 11:37:19 EDT

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    Lance, again I did not intend for this message to be broadcast. Your
    specific question is covered in the papers referenced below.


    If your customers understand the caveats and complexity, yet still choose to
    use that method, then you have served them well. Faced with the alternative
    of modifying site architecture, many customers knowingly make that choice,
    though from what I've seen, usually only as an interim solution to an
    unexpected problem.







    From: [] On Behalf Of Lance
    Sent: Thursday, July 15, 2004 7:20 AM
    Subject: RE: [load balancing] Alteon - Client Web Proxy Problems



    Did you write up an analysis on the weakness of site cookies and HTTP certs
    for site-specific domain names? I have been involved in several
    e-commerce deployments that required persistence and we have had good
    success with this solution.

    Maybe we are doing something different or we are not addressing the
    specific issue you have uncovered.

    At 01:55 PM 7/14/2004 -0700, Pete Tenereillo wrote:

    OK, looks like you just changed it now, in fact I can t even get to the
    CNAME any more, but the more basic question I guess do you have the Alteons
    themselves configured for RR? i.e. do you intend to balance traffic between
    sites? If so, you are going to definitely have issues with some ISPs/caches.
    It s pretty much the opposite problem to that described in the documents.
    The silver lining in the browser DNS cache is that it provides 30 min of
    persistence for free . Sounds like this problematic proxy is not one of
    those that caches TTLs for a fixed amount of time.


    There is a feature called DNS persistence that is available in the Alteon
    Content Director, but not in the standard WebOS. If you are OK with using
    single A records, that is probably what you need. I wrote a post that
    described it some time ago.


    There s also a really stupid solution peddled mostly by F5 et all which uses
    site cookies and HTTP certs for site-specific domain names. Alteon can offer
    this too with the integrated SSL offloader or even the standalone appliance,
    but they don t really push it and I m not sure it 100% works yet (there were
    issues when I left the company).






    From: [] On Behalf Of
    Giorgio Solari V.
    Sent: Wednesday, July 14, 2004 1:35 PM
    Subject: RE: [load balancing] Alteon - Client Web Proxy Problems


        Hi Pete, the configuration is set to answer only one IP. Thanks for the
    documents. But the problem persist.

    On Wed, 2004-07-14 at 15:24, Pete Tenereillo wrote:

    Giorgio, I just did a sniff, you are returning multiple A records on each
    resolution (the default on the Alteon, and most GSLBs for that matter).
    Likely either BIND on the Squid box, or the caching nameserver the Squid box
    is pointed at, is RRing those. You can shut off multiple A records on the
    Alteons, using the command:
    but then you will need to live with a reduced level of HA described here:
    Given it's ScotiaBank, HA is probably the primary objective of doing
    multisite in the first place.
    You can mitigate those potential problems somewhat by doing something like
    but you would still need to return single A records for the site-specific
    URLs (or you would be back to the original issue).
    The only bulletproof solution is to sync state between sites so that it does
    not matter what site a subsequent SSL session goes to. I know that's tough
    to do right.


    From: [] On Behalf Of
    Giorgio Solari V.
    Sent: Wednesday, July 14, 2004 11:25 AM
    Subject: [load balancing] Alteon - Client Web Proxy Problems


        Hello to all people. I nedd great aid. I formed two Alteon Application
    Switch 2208 (Version 21.0.4) successfully doing GSLB. The services are http
    and https. The problem I have is from certain clients that are behind some
    Web Proxy. Those proxy do not maintain the ssl (tcp) connection, changing
    the servant to the other alteon.

        Let me show a real log from a Squid proxy server which have the problem:

    1089670996.757 7955 TCP_MISS/200 564 CONNECT - DIRECT/ -
    1089670998.789 983 TCP_MISS/200 3145 CONNECT - DIRECT/ -
    1089671010.119 7658 TCP_MISS/200 2160 CONNECT - DIRECT/ -
    1089671010.550 8564 TCP_MISS/200 28085 CONNECT - DIRECT/ -
    1089671010.556 8306 TCP_MISS/200 32611 CONNECT - DIRECT/ -
    1089671010.556 8106 TCP_MISS/200 4071 CONNECT - DIRECT/ -
    1089671100.271 2795 TCP_MISS/200 3145 CONNECT - DIRECT/ -
    1089671118.082 16450 TCP_MISS/200 46618 CONNECT - DIRECT/ -
    1089671118.090 16229 TCP_MISS/200 14760 CONNECT - DIRECT/ -
    1089671118.090 11676 TCP_MISS/200 6357 CONNECT - DIRECT/ -
    1089671118.091 11675 TCP_MISS/200 760 CONNECT - DIRECT/ -
    1089671119.789 369 TCP_MISS/200 3145 CONNECT - DIRECT/ -
    1089671130.362 9426 TCP_MISS/200 9334 CONNECT - DIRECT/ -
    1089671130.384 9672 TCP_MISS/200 27865 CONNECT - DIRECT/ -
    1089671165.589 36409 TCP_MISS/200 27621 CONNECT - DIRECT/ -
    1089671165.603 36411 TCP_MISS/200 3721 CONNECT - DIRECT/ -
    1089671167.220 442 TCP_MISS/200 3157 CONNECT - DIRECT/ -
    1089671176.455 4578 TCP_MISS/200 5088 CONNECT - DIRECT/ -
    1089671176.519 39 TCP_MISS/200 39 CONNECT - DIRECT/ -

        I have tested a lot of proxy servers including squid, without problems.
    Somebody can help me please?. This it is the only ponit of fail that I have.




    Giorgio Solari V. <>
    Cientec S.A. 

    -- Giorgio Solari V. <> Cientec S.A.

    Lance McCallum

    Product Line Manager

    GSS and SCA

    1414 Massachusetts


    Boxborough, MA




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