Re: How to restart the root server from within modperl?
On Tue, Aug 12, 2003 at 11:50:01AM +0200, Dirk Lutzebaeck wrote: Dennis Stout writes: On a whim, I would try writing a second script to do the actual shutdown and restart of Apache. Then have your mod_perl program either run it in the background (with a ) or fork it into another process. Did exactly that but is has the effect that when the parent (root) apache is killed it kills all children including the script itself. So the server wont start again. Since you are talking about a management tool via http, you might consider using a second server process for this. If you select the 'restart link' then under water you need to (a) startup a server on a different port, (b) redirect to a URI on that server, (c) make it that that URI restarts the main server as you would normally do, (d) clean up the second server as soon as the main server restarts. You can do this in a sophisticated manner by creating a httpd config on the fly, using a unique restart-URI, thus avoiding the most obvious security risks. Might work... --Frank
Re: How to restart the root server from within modperl?
Martin Langhoff writes: how can I restart the root httpd server from within modperl? Use `at` to schedule it a minute in the future -- effectively forking it. Yes, also thought of that but the smallest unit of 'at' is minutes and I want to restart the server immediately. Note that normally apache starts as root and runs as an unprivileged user. If this is the case you _can_ achieve it using a suid wrapper or sudo, but you'll risk opening a very serious security hole in the system. So don't. Instead, run apache as a regular user, on a high port. I used sudo. Dirk
RE: How to restart the root server from within modperl?
In fact, I'm using 'killall httpd', which effectively kills every httpd process. The drawback is that you need /proc available and that it may kill httpd's belonging to another Apache. But afrer all, you can always write awk script that would parse ps output and do exactly what you want. Egor. One word of caution; killing just the parent httpd process will likely cause a lot of zombie processes since the parent process has died and will not be available to receive SIGCHLD. I don't have a solution, just thought I would offer a possible symptom to look out for. On Tue, 2003-08-12 at 12:38, Egor Shipovalov wrote: Why not start the Apache from a shell script that would always start it again if it dies? To restart the Apache then, you'd just kill the root httpd with apachectl. Killing the paernt shell script would terminate the whole operation. Egor. -Original Message- From: Dirk Lutzebaeck [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 12, 2003 1:17 To: [EMAIL PROTECTED] Subject: How to restart the root server from within modperl? Hi, how can I restart the root httpd server from within modperl? My problem is that when I call system() with say apachectl restart the father process is stopped killing the children including the apachectl itself. So it can't start of again. Can I call something like a reload of httpd.conf? Why I want to do this? I have a set of configurations and file links for different versions for my modperl application which I want to activate from the modperl application itself (having a HTML user interface). Thanks for help, Dirk --
Re: How to restart the root server from within modperl?
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
On Tuesday 12 August 2003 11:50, Dirk Lutzebaeck wrote:
Dennis Stout writes:
On a whim, I would try writing a second script to do the actual shutdown
and restart of Apache.
Then have your mod_perl program either run it in the background (with a
) or fork it into another process.
Did exactly that but is has the effect that when the parent (root)
apache is killed it kills all children including the script itself. So
the server wont start again.
I have done something like this several times. My code (it works since 1998 on
a highly used WEB Server with perl5.005_3) looks like that:
...
sub sysclose {
require 'syscall.ph';
syscall SYS_close, shift()+0;
}
sub RLIMIT_NOFILE {7;} # this is for LINUX
sub getrlimit {
require 'syscall.ph';
my $x=xx8; # result
syscall SYS_getrlimit, shift()+0, $x;
unpack ii, $x;
}
sub close_fd {
my @l=getrlimit( RLIMIT_NOFILE );
my $l;
for( $l=0; $l$l[0]; $l++ ) {
next if( $l==2 ); # close all file descriptors except of STDERR
sysclose $l;
}
}
sub disconnect_from_apache {
use POSIX qw/setsid/;
setsid;
close_fd;
}
...
my $child=fork;
unless( defined $child ) {
...
return OK;
}
if( $child ) {
my $child_status=0;
if( waitpid( $child, 0 )==$child ) {
$child_status=$?;
}
if( $child_status==0 ) {
...
return OK;
} else {
# The first fork succeeded but the second failed
...
return OK;
}
} else {
# Child process: fork again to detach from parent process
$child=fork;
CORE::exit( 0 ) if( $child ); # parent exits
unless( defined $child ) {
...
CORE::exit( 1 );
}
# Now we are the 2nd child process.
$self-disconnect_from_apache;
$self-doit( ... ); # == here comes the real code
CORE::exit( 0 );
}
...
$self-doit() is called in a separate process group and is not killed by a
signal sent to the apache process group. Further, all files save STDERR are
closed. This is needed since the code runs under mod_perl and the long
running child process inherits the open connection to the browser. If this
connection is not closed the browser shows an endless spinning globe or
something like that in the upper right corner.
Torsten
-BEGIN PGP SIGNATURE-
Version: GnuPG v1.0.7 (GNU/Linux)
iD8DBQE/OSIAwicyCTir8T4RAv3RAKCXdpbHLQepeOZFCyXt1KkMVGnwPgCeNu7X
hlC1NSEv0NsA7LlM7lol7wI=
=xId6
-END PGP SIGNATURE-
Re: How to restart the root server from within modperl?
Thanks, I made it a bit more simple:
use POSIX;
if (! fork) { # child
setsid;
POSIX::close(0);
POSIX::close(1);
exec(restart-apache-command);
}
Works great!
Thanks,
Dirk
Torsten Foertsch writes:
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
On Tuesday 12 August 2003 11:50, Dirk Lutzebaeck wrote:
Dennis Stout writes:
On a whim, I would try writing a second script to do the actual shutdown
and restart of Apache.
Then have your mod_perl program either run it in the background (with a
) or fork it into another process.
Did exactly that but is has the effect that when the parent (root)
apache is killed it kills all children including the script itself. So
the server wont start again.
I have done something like this several times. My code (it works since 1998 on
a highly used WEB Server with perl5.005_3) looks like that:
...
sub sysclose {
require 'syscall.ph';
syscall SYS_close, shift()+0;
}
sub RLIMIT_NOFILE {7;} # this is for LINUX
sub getrlimit {
require 'syscall.ph';
my $x=xx8; # result
syscall SYS_getrlimit, shift()+0, $x;
unpack ii, $x;
}
sub close_fd {
my @l=getrlimit( RLIMIT_NOFILE );
my $l;
for( $l=0; $l$l[0]; $l++ ) {
next if( $l==2 );# close all file descriptors except of STDERR
sysclose $l;
}
}
sub disconnect_from_apache {
use POSIX qw/setsid/;
setsid;
close_fd;
}
...
my $child=fork;
unless( defined $child ) {
...
return OK;
}
if( $child ) {
my $child_status=0;
if( waitpid( $child, 0 )==$child ) {
$child_status=$?;
}
if( $child_status==0 ) {
...
return OK;
} else {
# The first fork succeeded but the second failed
...
return OK;
}
} else {
# Child process: fork again to detach from parent process
$child=fork;
CORE::exit( 0 ) if( $child ); # parent exits
unless( defined $child ) {
...
CORE::exit( 1 );
}
# Now we are the 2nd child process.
$self-disconnect_from_apache;
$self-doit( ... ); # == here comes the real code
CORE::exit( 0 );
}
...
$self-doit() is called in a separate process group and is not killed by a
signal sent to the apache process group. Further, all files save STDERR are
closed. This is needed since the code runs under mod_perl and the long
running child process inherits the open connection to the browser. If this
connection is not closed the browser shows an endless spinning globe or
something like that in the upper right corner.
Torsten
-BEGIN PGP SIGNATURE-
Version: GnuPG v1.0.7 (GNU/Linux)
iD8DBQE/OSIAwicyCTir8T4RAv3RAKCXdpbHLQepeOZFCyXt1KkMVGnwPgCeNu7X
hlC1NSEv0NsA7LlM7lol7wI=
=xId6
-END PGP SIGNATURE-
RE: How to restart the root server from within modperl?
Can I call something like a reload of httpd.conf? This is what sending a SIGHUP to Apache does. However, both mod_perl-enabled servers I run misbehave on this, so I always do a full restart. Egor.
Re: How to restart the root server from within modperl?
how can I restart the root httpd server from within modperl? Use `at` to schedule it a minute in the future -- effectively forking it. Note that normally apache starts as root and runs as an unprivileged user. If this is the case you _can_ achieve it using a suid wrapper or sudo, but you'll risk opening a very serious security hole in the system. So don't. Instead, run apache as a regular user, on a high port. If you absolutely need to be in port 80, either setup a simple lightweight apache on port 80 as a reverse proxy (see the mod_perl guide) or, even simpler, do some port forwarding from port 80 to your high port of choice. regards, martin
RE: How to restart the root server from within modperl?
Why not start the Apache from a shell script that would always start it again if it dies? To restart the Apache then, you'd just kill the root httpd with apachectl. Killing the paernt shell script would terminate the whole operation. Egor. -Original Message- From: Dirk Lutzebaeck [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 12, 2003 1:17 To: [EMAIL PROTECTED] Subject: How to restart the root server from within modperl? Hi, how can I restart the root httpd server from within modperl? My problem is that when I call system() with say apachectl restart the father process is stopped killing the children including the apachectl itself. So it can't start of again. Can I call something like a reload of httpd.conf? Why I want to do this? I have a set of configurations and file links for different versions for my modperl application which I want to activate from the modperl application itself (having a HTML user interface). Thanks for help, Dirk
Re: How to restart the root server from within modperl?
Dennis Stout writes: On a whim, I would try writing a second script to do the actual shutdown and restart of Apache. Then have your mod_perl program either run it in the background (with a ) or fork it into another process. Did exactly that but is has the effect that when the parent (root) apache is killed it kills all children including the script itself. So the server wont start again. Dirk
