How many RBLs do you have in your RBL server list? What name server is your
SIMS machine using? It sounds like your RBL checks are taking long enough
that other servers trying to send messages to you are timing out while
waiting for your server to complete its RBL checks. If you've got a large
number of RBLs, you might try paring them down a bit. If the name server
that your SIMS machine uses to do DNS look-ups typically takes a long time
to respond, you might want to try changing to one that responds faster.
Also, make sure that the response addresses for the RBLs you use (typically
127.0.0.x) are in your SIMS' internal blacklist. Otherwise, all responses
to RBL checks will be considered negative and SIMS will have to wait for
all RBL queries to complete before proceeding with any given SMTP session.
A number of RBLs have also been under DOS attacks that seem to be perpetrated by spammers. It could be that one (or more) of the RBLs in your list is currently under attack and that your DNS requests to them are not being served properly.
############################################################# This message is sent to you because you are subscribed to the mailing list <[EMAIL PROTECTED]>. To unsubscribe, E-mail to: <[EMAIL PROTECTED]> To switch to the DIGEST mode, E-mail to <[EMAIL PROTECTED]> To switch to the INDEX mode, E-mail to <[EMAIL PROTECTED]> Send administrative queries to <[EMAIL PROTECTED]>
