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Hi Marian, On Tue, 1 Sep 2015, Marian Zvada wrote: > does anyone recall what's default value in xrootd for the caching file > status information? The default value is 8 hours. > I guess this is related to the cmsd process ... I'd like to know how often > refresh mechanism happens and if this is configurable value? Also, how to > force broadcast manually, does cmsd restart do it? It is configurable, please see: http://xrootd.org/doc/dev42/cms_config.htm#_Toc405927083 You can force a refesh of a file basis using the xrdfs command. For instance, xrdfs <redirector> locate -r <path> will look up <path> but not use any cached information. Technically, the cache is discarded for <path> prior to the lookup. > Yet another question: let's say the file exist only in certain location and > the sites' cmsd in the subscription chain horribly breaks, what happens? I If the site breaks (i.e. disconnects), the the site is marked as "bad" but the cached information is not dropped. That does not matter because no one will be sent to that site until it comes back. If it doesn't come back in 10 minutes, all cached infrmation about he site is dropped. > think, based on already cached information client is redirected to that > location but fails receive the file, correct? Meantime cache refresh takes > place and broadcasts information without this file present, so next time > there will be message to client "no servers..." ... Then site admin restarts > xrootd data server how long does usually take everyone else in the federation > know this file is present and accessible again from the restart point? Are > there any subtle things in the process to be aware of (like push restart of > cmsd in the hierarchy above etc)? Cached information is local to each cmsd in the hiearachy. Yes, restarting a cmsd kills the cache because it is in-memory. After a restart, lookups occur in the natural way and the cache is rebuilt. There is no time-lag here. Obvously, a restarted cmsd which asks another cmsd about a file that it has already cached, the response from that cmsd will be based on the cached information in that cmsd. Endpoints never cache information. Andy ######################################################################## 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