-## $Cambridge: exim/doc/doc-src/FAQ.src,v 1.5 2004/11/12 15:03:40 ph10 Exp $
+## $Cambridge: exim/doc/doc-src/FAQ.src,v 1.8 2009/11/05 19:37:00 nm4 Exp $
##
## This file is processed by Perl scripts to produce an ASCII and an HTML
## version. Lines starting with ## are omitted. The markup used with paragraphs
You can test the link using pings of large packets and see what works:
-==> ping -s host 2048
+==> ping -s host 2048
Try reducing the MTU on the sending host:
-==> ifconfig le0 mtu 1300
+==> ifconfig le0 mtu 1300
Alternatively, you can reduce the size of the buffer Exim uses for SMTP
output by putting something like
==> deny hosts = *.x.example
If at all possible, you should use IP addresses instead of host
- names in blocking lists in order to to avoid this problem.
+ names in blocking lists in order to avoid this problem.
You can use the \-bh-\ option to get more information about what is
happening at the start of a connection. However, note that the \-bh-\
second solution is used, users can empty their mailboxes by updating
them, but cannot delete them.
- If your problem involves mail to \/root/\, see also Q0507.
+ If your problem involves mail to \/root/\, see also Q0039.
Q0037: I am experiencing mailbox locking problems with Sun's \"mailtool"\ used
If you are running Exim with an alternate configuration file using a
command such as \"exim -C altconfig..."\, remember that the use of -C
- takes away Exim's root privilege.
+ takes away Exim's root privilege, unless \\TRUSTED_CONFIG_LIST\\
+ is set in \(Local/Makefile)\ and the corresponding file contains a
+ prefix which matches the alternative configuration file being used.
Check that you have defined the spool directory correctly by running
trying to run an \%autoreply%\ transport. Why is this?
A0065: When Exim is called with -C, it passes on -C to any instances of itself
- that it calls (so that the whole sequence uses the same config file). If
- it's running as \/exim/\ when it does this, all is well. However, if it
- happens as a consequence of a non-privileged user running \%autoreply%\,
- the called Exim gives up its root privilege. Then it can't write to the
- spool.
-
- This means that you can't use -C (even as \/root/\) to run an instance of
- Exim that is going to try to run \%autoreply%\ from a process that is
- neither \/root/\ nor \/exim/\. Because of the architecture of Exim (using
- re-execs to regain privilege), there isn't any way round this
- restriction. Therefore, the only way you can make this scenario work is
- to run the \%autoreply%\ transport as \/exim/\ (that is, the user that
- owns the Exim spool files). This may be satisfactory for autoreplies
- that are essentially system-generated, but of course is no good for
- autoreplies from unprivileged users, where you want the \%autoreply%\
- transport to be run as the user. To get that to work with an alternate
- configuration, you'll have to use two Exim binaries, with different
- configuration file names in each. See S001 for a script that patches
- the configuration name in an Exim binary.
+ that it calls (so that the whole sequence uses the same config file).
+ However, Exim gives up its root privilege if any user except \/root\/
+ passes a -C option to use a non-default configuration file, and that
+ includes the case where Exim re-execs itself to regain root privilege.
+ Thus it can't write to the spool.
+
+ The fix for this is to use the \\TRUSTED_CONFIG_LIST\\ build-time
+ option. This defines a file containing a list of 'trusted' prefixes for
+ configuration files. Any configuration file specified with -C, if it
+ matches a prefix listed in that file, will be used without dropping root
+ privileges (as long as it is not writeable by a non-root user).
Q0066: What does the message \*unable to set gid=xxx or uid=xxx*\ mean?
by a \"mail.info"\ descriptor).
Test this by running the command:
-==> logger -p mail.notice test
+==> logger -p mail.notice test
and seeing which logs it goes into. From Exim release 4.31 it is
possible to disable the rejectlog by setting \write_rejectlog\ false.
ensure that this happens throughout the build, it's best to export it in
your environment:
-==> MAKEFLAGS='-B'
- export MAKEFLAGS
- make
+==> MAKEFLAGS='-B'
+ export MAKEFLAGS
+ make
Q0116: I have tried to build Exim with Berkeley DB 3 and 4, but I always get
==> # Don't allow domains whose single MX (or A) record is a
# "special-use IPv4 address", as listed in RFC 3330.
ignore_target_hosts = \
- # Hosts on "this network"; RFC 1700 (page 4) states that these
- # are only allowed as source addresses
- 0.0.0.0/8 : \
- # Private networks, RFC 1918
- 10.0.0.0/8 : 172.16.0.0/12 : 192.168.0.0/16 : \
- # Internet host loopback address, RFC 1700 (page 5)
- 127.0.0.0/8 : \
- # "Link local" block
- 169.254.0.0/16 : \
- # "TEST-NET" - should not appear on the public Internet
- 192.0.2.0/24 : \
- # 6to4 relay anycast addresses, RFC 3068
- 192.88.99.0/24 : \
- # Network interconnect device benchmark testing, RFC 2544
- 198.18.0.0/15 : \
- # Multicast addresses, RFC 3171
- 224.0.0.0/4 : \
- # Reserved for future use, RFC 1700 (page 4)
- 240.0.0.0/4
+ # Hosts on "this network"; RFC 1700 (page 4) states that these
+ # are only allowed as source addresses
+ 0.0.0.0/8 : \
+ # Private networks, RFC 1918
+ 10.0.0.0/8 : 172.16.0.0/12 : 192.168.0.0/16 : \
+ # Internet host loopback address, RFC 1700 (page 5)
+ 127.0.0.0/8 : \
+ # "Link local" block
+ 169.254.0.0/16 : \
+ # "TEST-NET" - should not appear on the public Internet
+ 192.0.2.0/24 : \
+ # 6to4 relay anycast addresses, RFC 3068
+ 192.88.99.0/24 : \
+ # Network interconnect device benchmark testing, RFC 2544
+ 198.18.0.0/15 : \
+ # Multicast addresses, RFC 3171
+ 224.0.0.0/4 : \
+ # Reserved for future use, RFC 1700 (page 4)
+ 240.0.0.0/4
Q0320: How can I arrange for all mail to \*user@some.domain*\ to be forwarded
Q0409: I want mail for any local part at certain virtual domains to go
to a single address for each domain.
-A0409: One way to to this is
+A0409: One way to do this is
==> virtual:
driver = redirect
transport could be:
==> local_delivery_mbx:
- driver = pipe
- command = /usr/local/bin/tmail $local_part
- user = exim
- current_directory = /
+ driver = pipe
+ command = /usr/local/bin/tmail $local_part
+ user = exim
+ current_directory = /
use_crlf
message_prefix =
==> deny message = ${lookup{$sender_address=>$local_part@$domain}\
lsearch{/that/file}}
condition = ${lookup{$sender_address=>$local_part@$domain}\
- lsearch{/that/file}}{yes}{no}}
+ lsearch{/that/file}{yes}{no}}
The condition is tested first. If the lookup succeeds, the condition
succeeds so access is denied. The message is then expanded, but the
do not block legitimate mail. With that proviso, you can do it using
something like this in an ACL:
-==> drop message = HELO doesn't look like a hostname
- log_message = Not a hostname
- condition = ${if match{$sender_helo_name} \
- {\N^[^.].*\.[^.]+$\N}{no}{yes}}
+==> drop message = HELO doesn't look like a hostname
+ log_message = Not a hostname
+ condition = ${if match{$sender_helo_name} \
+ {\N^[^.].*\.[^.]+$\N}{no}{yes}}
This means: Drop the HELO unless it contains a dot somewhere in the HELO
string, but the string may not begin or end with a dot. Thus, the
names, but if mail comes in for an upper case login name, it doesn't
get rewritten.
-==> *@my.domain ${lookup{$1}dbm{/usr/lib/exim/longforms}\
- {$value}fail}@my.domain bcfrtFT
+==> *@my.domain ${lookup{$1}dbm{/usr/lib/exim/longforms}\
+ {$value}fail}@my.domain bcfrtFT
The longforms database has entries of the form:
are rewriting. If you are rewriting recipient addresses for your local
domain, you can do:
-==> *@dom.ain ${lookup{$1}dbm{/wher/ever}{$value}{failaddr}} Ehq
+==> *@dom.ain ${lookup{$1}dbm{/wher/ever}{$value}{failaddr}} Ehq
and in your alias file put something like
-==> failaddr: :fail: Rewriting failed
+==> failaddr: :fail: Rewriting failed
This fails a single recipient - others are processed independently.
encrypt the user/site/leaf certificate. If this isn't acceptable,
you seem to be able to strip out the passphrase as follows:
-==> openssl rsa -in user.key -our user.key.new
- mv user.key.new
+==> openssl rsa -in user.key -our user.key.new
+ mv user.key.new
This should be done immediately after \(user.key)\ is created.
==> # Now System is up, Modify kernel parameters for max open etc.
==> if [ -f /proc/sys/kernel/file-max ]; then
- echo 16384 >> /proc/sys/kernel/file-max
+ echo 16384 >> /proc/sys/kernel/file-max
fi
if [ -f /proc/sys/kernel/inode-max ]; then
- echo 24576 >> /proc/sys/kernel/inode-max
+ echo 24576 >> /proc/sys/kernel/inode-max
fi
if [ -f /proc/sys/kernel/file-nr ]; then
- echo 2160 >> /proc/sys/kernel/file-nr
+ echo 2160 >> /proc/sys/kernel/file-nr
fi
By echoing the value you want for file-max to the file \(file-max)\ etc.,
git://git.exim.org / exim.git / blobdiff