I have two problems. Problem #1: I've installed the big concurrency patch successfully and yet I cannot get above 257 connections at once. I'm using Debian Linux 2.2.18pre21 and from what I read, it should be quite possible to adjust the maximum processes per user through 'limit' (or 'ulimit' depending on the shell) rather than adjusting and recompiling the kernel. Well, I'm root, I do the adjustments to limit ('limit maxproc 1000') but when I check the logs, qmail never gets above 257 concurrency (256 is the default limit of maxproc). I do a 'limit' before and after I run my script and get the following output each time: cputime unlimited filesize unlimited datasize unlimited stacksize 8192 kbytes coredumpsize 0 kbytes memoryuse unlimited descriptors 10000 memorylocked unlimited maxproc 1000 openfiles 10000 So the limit adjustment is sticking and yet it's being ignored. I thought at one point that maybe when I change the limit as root it doesn't apply to user qmailr (the user opening all the connections) but when I 'su qmailr' and check 'limit' I get the same updated numbers so that doesn't seem to be the problem. In the logfiles, the error I get at 257 concurrent connections is this: May 2 16:21:07 debian qmail: 988845667.036121 status: local 0/10 remote 257/500 May 2 16:21:07 debian qmail: 988845667.036150 delivery 44180: deferral: qmail-spawn_unabl e_to_fork._(#4.3.0)/ May 2 16:21:07 debian qmail: 988845667.036176 status: local 0/10 remote 256/500 May 2 16:21:07 debian qmail: 988845667.036210 delivery 43746: success: 64.4.56.199_accept ed_message./Remote_host_said:_250_Requested_mail_action_okay,_completed/ "qmail-spawn unable to fork" pretty much tells me it's a linux resource problem. Okay, but what are 'limit' and 'ulimit' for if the adjustments I make to them are ignored? I realize this is more of a Linux question than a qmail one but at the same time, I know it's something many qmail users must have run into so I'm hoping I can get some feedback. Thanks. Problem #2: Is there a limit on the maximum number of Bccs you can have for a single message? I ask because somewhere between 5600 and 5700 Bccs qmail-inject stops trying. That is, I can send one message Bcced to 5600 people fine. But when I try to send the same message Bcced to 5700 people, qmail doesn't even try. The logs don't show that anything took place whatsoever. I suppose this could be another Linux resource issue but then wouldn't qmail at least try to send the message and then give me an error like it does above when it can't fork? Also puzzling is the fact that I *can* do this: call qmail-inject twice in a row, each time with 5600 recipients and qmail sends all 11200 messages fine. Here's qmail-showctl: qmail home directory: /var/qmail. user-ext delimiter: -. paternalism (in decimal): 2. silent concurrency limit: 500. subdirectory split: 23. user ids: 1001, 1002, 1003, 0, 1004, 1005, 1006, 1007. group ids: 1001, 64010. badmailfrom: (Default.) Any MAIL FROM is allowed. bouncefrom: (Default.) Bounce user name is MAILER-DAEMON. bouncehost: (Default.) Bounce host name is debian.wnrg.com. concurrencylocal: (Default.) Local concurrency is 10. concurrencyremote: Remote concurrency is 500. databytes: (Default.) SMTP DATA limit is 0 bytes. defaultdomain: Default domain name is wnrg.com. defaulthost: (Default.) Default host name is debian.wnrg.com. doublebouncehost: (Default.) 2B recipient host: debian.wnrg.com. doublebounceto: (Default.) 2B recipient user: postmaster. envnoathost: (Default.) Presumed domain name is debian.wnrg.com. helohost: (Default.) SMTP client HELO host name is debian.wnrg.com. idhost: (Default.) Message-ID host name is debian.wnrg.com. localiphost: (Default.) Local IP address becomes debian.wnrg.com. locals: Messages for debian.wnrg.com are delivered locally. Messages for debian.wnrg.com are delivered locally. me: My name is debian.wnrg.com. percenthack: (Default.) The percent hack is not allowed. plusdomain: Plus domain name is wnrg.com. qmqpservers: (Default.) No QMQP servers. queuelifetime: (Default.) Message lifetime in the queue is 604800 seconds. rcpthosts: SMTP clients may send messages to recipients at wnrg.com. SMTP clients may send messages to recipients at debian.wnrg.com. SMTP clients may send messages to recipients at debian.wnrg.com. morercpthosts: (Default.) No effect. morercpthosts.cdb: (Default.) No effect. smtpgreeting: (Default.) SMTP greeting: 220 debian.wnrg.com. smtproutes: SMTP route: debian.wnrg.com:mail.wnrg.com timeoutconnect: (Default.) SMTP client connection timeout is 60 seconds. timeoutremote: (Default.) SMTP client data timeout is 1200 seconds. timeoutsmtpd: (Default.) SMTP server data timeout is 1200 seconds. virtualdomains: (Default.) No virtual domains. Thanks in advance to anyone patient enough to read through all this and at least point me in the right direction. Brett.