2010/4/9 <[email protected]>: > Send OpenAFS-devel mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.openafs.org/mailman/listinfo/openafs-devel > or, via email, send a message with subject or body 'help' to > [email protected] > Message: 2 > Date: Thu, 08 Apr 2010 10:56:49 -0400 > From: Dale Pontius <[email protected]> > To: [email protected] > Subject: Re: [OpenAFS-devel] [GSoC2010] the kafs project of OpenAFS > > I work for a large multinational, and my CellServDB file, for lack of a > better word - big. Dozens of cells and well over 100 cell (not file) > servers. Can you describe a little better how the AFSDB records can be > used to build a dynamic CellServDB structure, especially without picking > up all of the non-Company afs cell servers from public dns?
I know that, clients could get the cell's location from a DNS server. For cell www.openafs.org, I could get this cell's location with the dns query $dig www.openafs.org afsdb ;; QUESTION SECTION: ;www.openafs.org. IN AFSDB ;; ANSWER SECTION: www.openafs.org. 3596 IN CNAME openafs.org. openafs.org. 3600 IN AFSDB 1 andrew.e.kth.se. openafs.org. 3600 IN AFSDB 1 grand-opening.mit.edu. openafs.org. 3600 IN AFSDB 1 penn.central.org. this format is described in RFC1183 AFSDB has the following format: <owner> <ttl> <class> AFSDB <subtype> <hostname> The owner is the name of the AFS cell, followed by a trailing dot. The <hostname> field is a domain name of a host that has a server for the cell named by the owner name of the RR. A subtype, the value of which is a 16 bit integer. A subtype equal to '1' indicates a host with an AFS v3.0 Volume Location Server. The target is the FQDN (not an alias!) of the host providing the service, followed by a trailing dot. As OpenAFS documentation: If the client attempts to access an AFS cell not listed in CellServDB and afsd was started with the -afsdb option, the Cache Manager will attempt an AFSDB DNS record lookup and dynamically add the database server locations for that cell based on the result of the DNS query. But The CellServDB must exist however, even if it is empty. The cell name is needed, and OpenAFS will use DNS to find the servers. I have no idea about that how to optimize it if there are too many cells. I am not very clear about how to add the afsdb record to DNS. Maybe you should add it with yourself. I thought you could find that in the OpenAFS documentation. > Most would favor pushing as much into userspace as can be done well > there. Keep in the kernel only what needs to be in the kernel. Thank you, I think I would. > I like the idea of using kafs - really I'd just as soon use kafs with > the OpenAFS userspace. Nouveau is getting to the point of being usable, > removing the nVidia kernel taint. Only the OpenAFS kernel taint is > left, and kafs would get rid of that. > > Thanks, > > -- > Dale Pontius > Senior Engineer > IBM Corporation > Phone: (802) 769-6850 > Tie-Line: 446-6850 > email: [email protected] > Thank you for your advice. -- Best Wish. Wang Lei _______________________________________________ OpenAFS-devel mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-devel
