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On 27.3.2014 10:10, Tommaso Boccali wrote: > ok, but what happens if a site restarts its cmsd when the redirector > points just to one redirector (because the other is off)? > when the second redirector comes back in the DNS list, will the site > pick it up or not? that's I don't know, just my wild guess is nothing bad would happened from client side if you can keep up at least with one host from the DNS-RR. Also that's why my concern whether "all" or "any" while using "+" at the time. If someone has tested proposed scenario by you would be great share the knowledge. Thanks, Marian > thanks! > > tom > > > On Thu, Mar 27, 2014 at 4:08 PM, Marian Zvada <[log in to unmask] > <mailto:[log in to unmask]>> wrote: > > Hi Tommaso, > > we have very same setup for CMS T2 and currently in commissioning > process. We have DNS round-robin alias between FNAL and UNL and use > the following in the config: > > all.manager meta all cmsxrootd.fnal.gov <http://cmsxrootd.fnal.gov>+ > 1213 > (xrootd1.fnal.gov <http://xrootd1.fnal.gov> and xrootd.unl.edu > <http://xrootd.unl.edu> behind that) > > => I think this should be adapted also for your setup as well I > believe, though pointing to different aliased host. > > For the question of "all" as parameter I was already asking in > developers list what's beneficial, all || any, but didn't get > response so far. Here it's documented but I didn't get full > understanding what's recommended from operation point of view while > using DNS-RR setup: > http://xrootd.org/doc/prod/__cms_config.htm#_Toc339484334 > <http://xrootd.org/doc/prod/cms_config.htm#_Toc339484334> > > However, we stick so far with: > all.manager meta all cmsxrootd.fnal.gov <http://cmsxrootd.fnal.gov>+ > 1213 > > Also, currently each of top redirectors in the DNS-RR alias > subscribes to global redirector: > all.manager meta any cms-xrd-global.cern.ch > <http://cms-xrd-global.cern.ch>+ 1098 > (see 'any' in this case) > > Hope that helps. > > -Marian > > > On 27.3.2014 3:43, Tommaso Boccali wrote: > > Ciao, reading CMSD documentation I read > > > 2.1 manager > > ... > > 8) If the manager host name ends with a plus, then all the IP > addresses > associated with host are treated as managers and every non-manager > *cmsd* and *xrootd* subscribes to each one. This allows you to > easily > > construct fault-tolerant configurations using the IP address alias > feature in DNS. > > > > I would like to use this: we have a setup in which a regional > redirector > is replicated 2+ times, and all the redirectors are resolved via a > single DNS name, which reports 2+ IPs. > I understand cmsd upon start will connect to ALL of them, right? > > That said (supposing I understood correctly), I have a second > question: > the IPs returned via DNS queries are supposed to be changing > with time, > because we have automatic removal of those which are not ok at a > given > moment. > > What happens if a site starts cmsd when an IP is not present? If > later > that goes back in to the DNS, will it be picked up or the list of > manager is built statically at startup? > > thanks a lot > > tom > > -- > Tommaso Boccali > INFN Pisa > > ------------------------------__------------------------------__------------ > > Use REPLY-ALL to reply to list > > To unsubscribe from the XROOTD-L list, click the following link: > https://listserv.slac.__stanford.edu/cgi-bin/wa?__SUBED1=XROOTD-L&A=1 > <https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1> > <https://listserv.slac.__stanford.edu/cgi-bin/wa?__SUBED1=XROOTD-L&A=1 > <https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1>> > > > > > -- > Tommaso Boccali > INFN Pisa ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the XROOTD-L list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1