How to execute ejabberdctl command line administration script? reopen_log: Reopen the log files after they were renamed. Provide the delay in seconds, and the announcement quoted. The commands included in ejabberd by default are: stop_kindly delay announcement: Inform users and rooms, wait, and stop the server. Of course, the hosts list can contain just one domain if you do not want to host multiple XMPP domains on the same instance. The option hosts defines a list containing one or more domains that ejabberd will serve. It will also give you an option to embed a nice badge certifying you passed all the tests.Ĭan You host more than one domain in ejabberd? XMPP compliance test is a great way to know if your ejabberd is well configured and accessible. Your shiny new XMPP server is well worth it.How to know if your ejabberd is compliant with XMPP? We all know your pain, and we’re here to make it all better. So don’t feel bad when you’ve run into this problem and found this blog entry about how to fix it. This is a lot different than most Web servers which only need to handle a relatively small amount of simultaneously connected users, but very high traffic Web sites will also run into file descriptor shortages. Even if you don’t have many local users, there are a lot of XMPP servers out there. After all, no matter what language you use, you need one socket per connected client and one per federated server with whom you are communicating. While Erlang certainly helps eat file descriptors, I think the real issue is that XMPP daemons just need a lot of sockets, which just happen to be file descriptors. I hit it myself testing ejabberd for Chesspark, and now Identi.ca has been similarly bitten. Even the team bumped into this issue when ejabberd was put into production. Running out of file descriptors has bitten many a systems administrator. This can be done by editing /etc/security/nf and adding lines like these:ĭon’t Be Embarassed Even We Messed This Up On Linux it is necessary to increase the default allowed for a single user. Not only that but if you raise the limit as root and then launch ejabberd, which is run via su, the new shell will not inherit the limit. On typical machines doing this as a normal user will fail. The ulimit command will describe the current limits for the current shell, and ulimit -n NUM will request a new limit of NUM file descriptors. The normal way to fix this is to increase the file descriptor limit. With Erlang, this limit soon becomes constricting. Most operating systems of the Unix lineage give users a maximum of 1024 file descriptors to play with. 1024 File Descriptors Should Be Enough For Everyone All these processes can quickly start consuming a lot of file descriptors, and this is where things start to go wrong. You shouldn’t be alarmed by this however it’s just how Erlang was designed. This sounds like a lot, and compared to languages most of us are used to it is. Just as an example, Chesspark currently has 663 processes running and has over 22 thousand. In ejabberd, each client connection is a process, each server connection is a process, and processes are used to parallelize stanza handling in certain cases. :EXTENDED: How Many Processes Does It Take To Talk XMPP? This has tripped up many first time users of ejabberd, and it’s time someone explained how to deal with this. Erlang can host hundreds of thousands of processes, and one consequence of this is that Erlang loves to eat file descriptors. Even those that do know about this underestimate “lots” by an order of magnitude. Most people coming to Erlang for the first time don’t realize that it is designed to host lots of lightweight processes that communicate via message passing. Metajack.im - File Descriptors are Yummy or Common Pitfalls of Ejabberd blog books talks about File Descriptors are Yummy or Common Pitfalls of EjabberdĮrlang is different - really different.
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