>On Sat, 18 Feb 1995 14:10:08 -0600 Natalie Maynor said: >>> I'd like to learn how to checkout what is and isn't down so I can >>> intelligently answer the queries I am getting. When you ask about the "server being down" I believe you are really asking about end-to-end transmission. What constitutes E-2-E xmission? Here's a first pass (in no particular order): .telecom links (usually provisioned by the telephone company incl. long distance (IXC) and local operating companies (LEC) (and of course overseas circuits) .routers that xmit IP packets (the atomic unit of the Internet) .store-and-forward hosts such as those commonly found on bitnet e.g., UGA, PSUVM, SEARN (they need not be listserv hosts) .availability of authoritative hosts for the domain name system (these guys translate host names to IP address or to other mail exchangers (MX) e.g., NETCOM.COM has 16 MX hosts that can exchange i.e., receive mail .mail exchangers (MX) on the Internet .correctly configured RSCS (NJE), MAILER, LISTSERV, SENDMAIL software .correctly configured mail file systems with sufficient disk-space for the user .sufficient bandwidth of telecom links .sufficient horsepower (CPU and disk) of sending/intermediate/receiving sites Sometimes in trouble shooting, we find that the current configuration is NOW correct, but in the recent past there was a problem or change and that residual obsolete info STILL exists at intermediate sites pending a "timeout" of the cached info. There are plenty of samples of trouble shooting that have been broadcasted to LSTOWN-L and NODEINFO from such experts as Melvin Klassen (from whom I've learned alot). Tools such and various inquiries of RSCS, MAILER, SMTP, DNS (DiG or NSLOOKUP), LISTSERV (DISTRIBUTE MAIL DEBUG=YES wrt REVIEW list) are used. Sometimes they require you to be on that network: it might be impossible to inquiry of an RSCS Q from an Internet host. IMO, understanding "all" of this forms a career path. -- co-owner INFOSYS, TQM-L, CPARK-L, ERAPPA-L, JANITORS, LDBASE-L, et -L [log in to unmask] "Hot MIPS sink CHIPS" +1 814 863 1843 31 Shields Bldg. -- Penn State Univ -- University Park, PA 16802-1202 USA