How does one change the delay that occurs after entering an incorrect password?
Clash Royale CLAN TAG#URR8PPP
After entering an incorrect password at a login prompt, there s an approximately 3-second delay. How can I change that on a Linux system with PAM?
login pam hardening
edited Nov 4 '16 at 10:38
countermode
5,20841943
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
add a comment |
After entering an incorrect password at a login prompt, there s an approximately 3-second delay. How can I change that on a Linux system with PAM?
login pam hardening
edited Nov 4 '16 at 10:38
countermode
5,20841943
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
1
I get the need for a delay from a security perspective, but the default delay is rather annoying
– Mike Pennington
Jun 16 '12 at 21:41
3
This has been interesting; maybe I'll write a module that allows N tries with no delay followed by any number of tries with a long delay.
– Shawn J. Goff
Jun 16 '12 at 23:27
1
Instead of a new module (suggested in my previous comment), I usedpam_unixwith thenodelayoption andpam_tally2withdeny=5 unlock_time=15; this allows for 5 immediate retries, but denies access (even with a successful password) for 15 seconds. I still intend to try writing the described model, but now it's a back-burner project, because this would not be suitable if your primary access to the system is network-based since it makes a DOS attack trivial.
– Shawn J. Goff
Jun 20 '12 at 22:25
1
if you are concerned about a network DoS from timeouts, use fail2ban... in fact use it even if you think you're safe :-). i use two day ban times
– Mike Pennington
Jun 20 '12 at 23:18
add a comment |
After entering an incorrect password at a login prompt, there s an approximately 3-second delay. How can I change that on a Linux system with PAM?
login pam hardening
edited Nov 4 '16 at 10:38
countermode
5,20841943
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
After entering an incorrect password at a login prompt, there s an approximately 3-second delay. How can I change that on a Linux system with PAM?
login pam hardening
login pam hardening
edited Nov 4 '16 at 10:38
countermode
5,20841943
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
edited Nov 4 '16 at 10:38
countermode
5,20841943
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
edited Nov 4 '16 at 10:38
countermode
5,20841943
edited Nov 4 '16 at 10:38
countermode
5,20841943
edited Nov 4 '16 at 10:38
countermode
5,20841943
5,20841943
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
asked Jun 16 '12 at 16:37
Shawn J. Goff
29.3k19109134
29.3k19109134
1
I get the need for a delay from a security perspective, but the default delay is rather annoying
– Mike Pennington
Jun 16 '12 at 21:41
3
This has been interesting; maybe I'll write a module that allows N tries with no delay followed by any number of tries with a long delay.
– Shawn J. Goff
Jun 16 '12 at 23:27
1
Instead of a new module (suggested in my previous comment), I usedpam_unixwith thenodelayoption andpam_tally2withdeny=5 unlock_time=15; this allows for 5 immediate retries, but denies access (even with a successful password) for 15 seconds. I still intend to try writing the described model, but now it's a back-burner project, because this would not be suitable if your primary access to the system is network-based since it makes a DOS attack trivial.
– Shawn J. Goff
Jun 20 '12 at 22:25
1
if you are concerned about a network DoS from timeouts, use fail2ban... in fact use it even if you think you're safe :-). i use two day ban times
– Mike Pennington
Jun 20 '12 at 23:18
add a comment |
1
I get the need for a delay from a security perspective, but the default delay is rather annoying
– Mike Pennington
Jun 16 '12 at 21:41
3
This has been interesting; maybe I'll write a module that allows N tries with no delay followed by any number of tries with a long delay.
– Shawn J. Goff
Jun 16 '12 at 23:27
1
Instead of a new module (suggested in my previous comment), I usedpam_unixwith thenodelayoption andpam_tally2withdeny=5 unlock_time=15; this allows for 5 immediate retries, but denies access (even with a successful password) for 15 seconds. I still intend to try writing the described model, but now it's a back-burner project, because this would not be suitable if your primary access to the system is network-based since it makes a DOS attack trivial.
– Shawn J. Goff
Jun 20 '12 at 22:25
1
if you are concerned about a network DoS from timeouts, use fail2ban... in fact use it even if you think you're safe :-). i use two day ban times
– Mike Pennington
Jun 20 '12 at 23:18
1
1
I get the need for a delay from a security perspective, but the default delay is rather annoying
– Mike Pennington
Jun 16 '12 at 21:41
I get the need for a delay from a security perspective, but the default delay is rather annoying
– Mike Pennington
Jun 16 '12 at 21:41
3
3
This has been interesting; maybe I'll write a module that allows N tries with no delay followed by any number of tries with a long delay.
– Shawn J. Goff
Jun 16 '12 at 23:27
This has been interesting; maybe I'll write a module that allows N tries with no delay followed by any number of tries with a long delay.
– Shawn J. Goff
Jun 16 '12 at 23:27
1
1
Instead of a new module (suggested in my previous comment), I used
pam_unix with the nodelay option and pam_tally2 with deny=5 unlock_time=15; this allows for 5 immediate retries, but denies access (even with a successful password) for 15 seconds. I still intend to try writing the described model, but now it's a back-burner project, because this would not be suitable if your primary access to the system is network-based since it makes a DOS attack trivial.– Shawn J. Goff
Jun 20 '12 at 22:25
Instead of a new module (suggested in my previous comment), I used
pam_unix with the nodelay option and pam_tally2 with deny=5 unlock_time=15; this allows for 5 immediate retries, but denies access (even with a successful password) for 15 seconds. I still intend to try writing the described model, but now it's a back-burner project, because this would not be suitable if your primary access to the system is network-based since it makes a DOS attack trivial.– Shawn J. Goff
Jun 20 '12 at 22:25
1
1
if you are concerned about a network DoS from timeouts, use fail2ban... in fact use it even if you think you're safe :-). i use two day ban times
– Mike Pennington
Jun 20 '12 at 23:18
if you are concerned about a network DoS from timeouts, use fail2ban... in fact use it even if you think you're safe :-). i use two day ban times
– Mike Pennington
Jun 20 '12 at 23:18
add a comment |
2 Answers
2
active
oldest
votes
I assume you are using Linux and pam. The delay is probably caused by pam_faildelay.so. Check your pam configuration in /etc/pam.d using pam_faildelay, e.g:
# Enforce a minimal delay in case of failure (in microseconds).
# (Replaces the `FAIL_DELAY' setting from login.defs)
# Note that other modules may require another minimal delay. (for example,
# to disable any delay, you should add the nodelay option to pam_unix)
auth optional pam_faildelay.so delay=3000000
To change the time adjust the delay parameter. If you want to get rid of the delay you can delete/comment the complete line.
Another source for the delay may be pam_unix.so. To disable the delay caused by pam_unix.so add the nodelay parameter, and optionally add a line calling pam_faildelay.so to add a (variable) delay instead, e.g.:
auth optional pam_faildelay.so delay=100000
edited Dec 14 at 20:15
Tim
1635
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
2
There is no mention of delay anywhere in/etc/pam.d/*. The closest thing I see ispam_tally.sowhich allows locking after some number of attempts. But I do have n/etc/login.defs, which might be what I need.
– Shawn J. Goff
Jun 16 '12 at 16:53
@ShawnJ.Goffpam_tally.sodoes not cause an delay as far as i know. Another source for the dealy may bepam_unix.so- you can disable it with thenodelayoption - see linux.die.net/man/8/pam_unix for more details
– Ulrich Dangel
Jun 16 '12 at 17:07
1
Adding thenodelayoption topam_unix.soand adding a new entry withpam_faildelay.so delay=$some_numberlets me set whatever I want. Thanks!
– Shawn J. Goff
Jun 16 '12 at 22:13
1
Running fedora 23, I had to disable thepam_unix.sodelay and start using thepam_faildelay.soone as @ShawnJ.Goff says. However, mostpam.dconfigs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?
– jozxyqk
Jan 29 '16 at 7:34
add a comment |
You need to pass the nodelay parameter to the auth pam_unix.so.
Depending on how your'e authenticating, where you need to set the parameter varies. However most linux distrubtions have something like /etc/pam.d/system-auth which is included by all the different files.
So for example in /etc/pam.d/system-auth you might have a line that looks like this:
auth sufficient pam_unix.so try_first_pass nullok
This should be changed to:
auth sufficient pam_unix.so try_first_pass nullok nodelay
The pam_unix.so module is what performs authentication against /etc/passwd and /etc/shadow. If youre using LDAP or some other password backend, you likely should still be setting nodelay on the pam_unix.so as that is what controls the prompt (when pam_unix.so fails to auth, it usually just passes the password it obtained to the next module).
You can read more about pam_unix.so by doing man pam_unix
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
On my systemsystem-authdid not exist; it was/etc/common-auth. Thanks!
– Luc
Jul 30 '16 at 20:41
add a comment |
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2 Answers
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active
oldest
votes
2 Answers
2
active
oldest
votes
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I assume you are using Linux and pam. The delay is probably caused by pam_faildelay.so. Check your pam configuration in /etc/pam.d using pam_faildelay, e.g:
# Enforce a minimal delay in case of failure (in microseconds).
# (Replaces the `FAIL_DELAY' setting from login.defs)
# Note that other modules may require another minimal delay. (for example,
# to disable any delay, you should add the nodelay option to pam_unix)
auth optional pam_faildelay.so delay=3000000
To change the time adjust the delay parameter. If you want to get rid of the delay you can delete/comment the complete line.
Another source for the delay may be pam_unix.so. To disable the delay caused by pam_unix.so add the nodelay parameter, and optionally add a line calling pam_faildelay.so to add a (variable) delay instead, e.g.:
auth optional pam_faildelay.so delay=100000
edited Dec 14 at 20:15
Tim
1635
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
2
There is no mention of delay anywhere in/etc/pam.d/*. The closest thing I see ispam_tally.sowhich allows locking after some number of attempts. But I do have n/etc/login.defs, which might be what I need.
– Shawn J. Goff
Jun 16 '12 at 16:53
@ShawnJ.Goffpam_tally.sodoes not cause an delay as far as i know. Another source for the dealy may bepam_unix.so- you can disable it with thenodelayoption - see linux.die.net/man/8/pam_unix for more details
– Ulrich Dangel
Jun 16 '12 at 17:07
1
Adding thenodelayoption topam_unix.soand adding a new entry withpam_faildelay.so delay=$some_numberlets me set whatever I want. Thanks!
– Shawn J. Goff
Jun 16 '12 at 22:13
1
Running fedora 23, I had to disable thepam_unix.sodelay and start using thepam_faildelay.soone as @ShawnJ.Goff says. However, mostpam.dconfigs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?
– jozxyqk
Jan 29 '16 at 7:34
add a comment |
I assume you are using Linux and pam. The delay is probably caused by pam_faildelay.so. Check your pam configuration in /etc/pam.d using pam_faildelay, e.g:
# Enforce a minimal delay in case of failure (in microseconds).
# (Replaces the `FAIL_DELAY' setting from login.defs)
# Note that other modules may require another minimal delay. (for example,
# to disable any delay, you should add the nodelay option to pam_unix)
auth optional pam_faildelay.so delay=3000000
To change the time adjust the delay parameter. If you want to get rid of the delay you can delete/comment the complete line.
Another source for the delay may be pam_unix.so. To disable the delay caused by pam_unix.so add the nodelay parameter, and optionally add a line calling pam_faildelay.so to add a (variable) delay instead, e.g.:
auth optional pam_faildelay.so delay=100000
edited Dec 14 at 20:15
Tim
1635
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
2
There is no mention of delay anywhere in/etc/pam.d/*. The closest thing I see ispam_tally.sowhich allows locking after some number of attempts. But I do have n/etc/login.defs, which might be what I need.
– Shawn J. Goff
Jun 16 '12 at 16:53
@ShawnJ.Goffpam_tally.sodoes not cause an delay as far as i know. Another source for the dealy may bepam_unix.so- you can disable it with thenodelayoption - see linux.die.net/man/8/pam_unix for more details
– Ulrich Dangel
Jun 16 '12 at 17:07
1
Adding thenodelayoption topam_unix.soand adding a new entry withpam_faildelay.so delay=$some_numberlets me set whatever I want. Thanks!
– Shawn J. Goff
Jun 16 '12 at 22:13
1
Running fedora 23, I had to disable thepam_unix.sodelay and start using thepam_faildelay.soone as @ShawnJ.Goff says. However, mostpam.dconfigs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?
– jozxyqk
Jan 29 '16 at 7:34
add a comment |
I assume you are using Linux and pam. The delay is probably caused by pam_faildelay.so. Check your pam configuration in /etc/pam.d using pam_faildelay, e.g:
# Enforce a minimal delay in case of failure (in microseconds).
# (Replaces the `FAIL_DELAY' setting from login.defs)
# Note that other modules may require another minimal delay. (for example,
# to disable any delay, you should add the nodelay option to pam_unix)
auth optional pam_faildelay.so delay=3000000
To change the time adjust the delay parameter. If you want to get rid of the delay you can delete/comment the complete line.
Another source for the delay may be pam_unix.so. To disable the delay caused by pam_unix.so add the nodelay parameter, and optionally add a line calling pam_faildelay.so to add a (variable) delay instead, e.g.:
auth optional pam_faildelay.so delay=100000
edited Dec 14 at 20:15
Tim
1635
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
I assume you are using Linux and pam. The delay is probably caused by pam_faildelay.so. Check your pam configuration in /etc/pam.d using pam_faildelay, e.g:
# Enforce a minimal delay in case of failure (in microseconds).
# (Replaces the `FAIL_DELAY' setting from login.defs)
# Note that other modules may require another minimal delay. (for example,
# to disable any delay, you should add the nodelay option to pam_unix)
auth optional pam_faildelay.so delay=3000000
To change the time adjust the delay parameter. If you want to get rid of the delay you can delete/comment the complete line.
Another source for the delay may be pam_unix.so. To disable the delay caused by pam_unix.so add the nodelay parameter, and optionally add a line calling pam_faildelay.so to add a (variable) delay instead, e.g.:
auth optional pam_faildelay.so delay=100000
edited Dec 14 at 20:15
Tim
1635
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
edited Dec 14 at 20:15
Tim
1635
edited Dec 14 at 20:15
Tim
1635
edited Dec 14 at 20:15
Tim
1635
1635
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
answered Jun 16 '12 at 16:44
Ulrich Dangel
20.3k25771
20.3k25771
2
There is no mention of delay anywhere in/etc/pam.d/*. The closest thing I see ispam_tally.sowhich allows locking after some number of attempts. But I do have n/etc/login.defs, which might be what I need.
– Shawn J. Goff
Jun 16 '12 at 16:53
@ShawnJ.Goffpam_tally.sodoes not cause an delay as far as i know. Another source for the dealy may bepam_unix.so- you can disable it with thenodelayoption - see linux.die.net/man/8/pam_unix for more details
– Ulrich Dangel
Jun 16 '12 at 17:07
1
Adding thenodelayoption topam_unix.soand adding a new entry withpam_faildelay.so delay=$some_numberlets me set whatever I want. Thanks!
– Shawn J. Goff
Jun 16 '12 at 22:13
1
Running fedora 23, I had to disable thepam_unix.sodelay and start using thepam_faildelay.soone as @ShawnJ.Goff says. However, mostpam.dconfigs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?
– jozxyqk
Jan 29 '16 at 7:34
add a comment |
2
There is no mention of delay anywhere in/etc/pam.d/*. The closest thing I see ispam_tally.sowhich allows locking after some number of attempts. But I do have n/etc/login.defs, which might be what I need.
– Shawn J. Goff
Jun 16 '12 at 16:53
@ShawnJ.Goffpam_tally.sodoes not cause an delay as far as i know. Another source for the dealy may bepam_unix.so- you can disable it with thenodelayoption - see linux.die.net/man/8/pam_unix for more details
– Ulrich Dangel
Jun 16 '12 at 17:07
1
Adding thenodelayoption topam_unix.soand adding a new entry withpam_faildelay.so delay=$some_numberlets me set whatever I want. Thanks!
– Shawn J. Goff
Jun 16 '12 at 22:13
1
Running fedora 23, I had to disable thepam_unix.sodelay and start using thepam_faildelay.soone as @ShawnJ.Goff says. However, mostpam.dconfigs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?
– jozxyqk
Jan 29 '16 at 7:34
2
2
There is no mention of delay anywhere in
/etc/pam.d/*. The closest thing I see is pam_tally.so which allows locking after some number of attempts. But I do have n /etc/login.defs, which might be what I need.– Shawn J. Goff
Jun 16 '12 at 16:53
There is no mention of delay anywhere in
/etc/pam.d/*. The closest thing I see is pam_tally.so which allows locking after some number of attempts. But I do have n /etc/login.defs, which might be what I need.– Shawn J. Goff
Jun 16 '12 at 16:53
@ShawnJ.Goff
pam_tally.so does not cause an delay as far as i know. Another source for the dealy may be pam_unix.so - you can disable it with the nodelay option - see linux.die.net/man/8/pam_unix for more details– Ulrich Dangel
Jun 16 '12 at 17:07
@ShawnJ.Goff
pam_tally.so does not cause an delay as far as i know. Another source for the dealy may be pam_unix.so - you can disable it with the nodelay option - see linux.die.net/man/8/pam_unix for more details– Ulrich Dangel
Jun 16 '12 at 17:07
1
1
Adding the
nodelay option to pam_unix.so and adding a new entry with pam_faildelay.so delay=$some_number lets me set whatever I want. Thanks!– Shawn J. Goff
Jun 16 '12 at 22:13
Adding the
nodelay option to pam_unix.so and adding a new entry with pam_faildelay.so delay=$some_number lets me set whatever I want. Thanks!– Shawn J. Goff
Jun 16 '12 at 22:13
1
1
Running fedora 23, I had to disable the
pam_unix.so delay and start using the pam_faildelay.so one as @ShawnJ.Goff says. However, most pam.d configs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?– jozxyqk
Jan 29 '16 at 7:34
Running fedora 23, I had to disable the
pam_unix.so delay and start using the pam_faildelay.so one as @ShawnJ.Goff says. However, most pam.d configs have "This file is auto-generated. User changes will be destroyed the next time authconfig is run." So where can I permanently configure the delay?– jozxyqk
Jan 29 '16 at 7:34
add a comment |
You need to pass the nodelay parameter to the auth pam_unix.so.
Depending on how your'e authenticating, where you need to set the parameter varies. However most linux distrubtions have something like /etc/pam.d/system-auth which is included by all the different files.
So for example in /etc/pam.d/system-auth you might have a line that looks like this:
auth sufficient pam_unix.so try_first_pass nullok
This should be changed to:
auth sufficient pam_unix.so try_first_pass nullok nodelay
The pam_unix.so module is what performs authentication against /etc/passwd and /etc/shadow. If youre using LDAP or some other password backend, you likely should still be setting nodelay on the pam_unix.so as that is what controls the prompt (when pam_unix.so fails to auth, it usually just passes the password it obtained to the next module).
You can read more about pam_unix.so by doing man pam_unix
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
On my systemsystem-authdid not exist; it was/etc/common-auth. Thanks!
– Luc
Jul 30 '16 at 20:41
add a comment |
You need to pass the nodelay parameter to the auth pam_unix.so.
Depending on how your'e authenticating, where you need to set the parameter varies. However most linux distrubtions have something like /etc/pam.d/system-auth which is included by all the different files.
So for example in /etc/pam.d/system-auth you might have a line that looks like this:
auth sufficient pam_unix.so try_first_pass nullok
This should be changed to:
auth sufficient pam_unix.so try_first_pass nullok nodelay
The pam_unix.so module is what performs authentication against /etc/passwd and /etc/shadow. If youre using LDAP or some other password backend, you likely should still be setting nodelay on the pam_unix.so as that is what controls the prompt (when pam_unix.so fails to auth, it usually just passes the password it obtained to the next module).
You can read more about pam_unix.so by doing man pam_unix
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
On my systemsystem-authdid not exist; it was/etc/common-auth. Thanks!
– Luc
Jul 30 '16 at 20:41
add a comment |
You need to pass the nodelay parameter to the auth pam_unix.so.
Depending on how your'e authenticating, where you need to set the parameter varies. However most linux distrubtions have something like /etc/pam.d/system-auth which is included by all the different files.
So for example in /etc/pam.d/system-auth you might have a line that looks like this:
auth sufficient pam_unix.so try_first_pass nullok
This should be changed to:
auth sufficient pam_unix.so try_first_pass nullok nodelay
The pam_unix.so module is what performs authentication against /etc/passwd and /etc/shadow. If youre using LDAP or some other password backend, you likely should still be setting nodelay on the pam_unix.so as that is what controls the prompt (when pam_unix.so fails to auth, it usually just passes the password it obtained to the next module).
You can read more about pam_unix.so by doing man pam_unix
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
You need to pass the nodelay parameter to the auth pam_unix.so.
Depending on how your'e authenticating, where you need to set the parameter varies. However most linux distrubtions have something like /etc/pam.d/system-auth which is included by all the different files.
So for example in /etc/pam.d/system-auth you might have a line that looks like this:
auth sufficient pam_unix.so try_first_pass nullok
This should be changed to:
auth sufficient pam_unix.so try_first_pass nullok nodelay
The pam_unix.so module is what performs authentication against /etc/passwd and /etc/shadow. If youre using LDAP or some other password backend, you likely should still be setting nodelay on the pam_unix.so as that is what controls the prompt (when pam_unix.so fails to auth, it usually just passes the password it obtained to the next module).
You can read more about pam_unix.so by doing man pam_unix
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
answered Jun 16 '12 at 19:31
Patrick
49.8k11127178
49.8k11127178
On my systemsystem-authdid not exist; it was/etc/common-auth. Thanks!
– Luc
Jul 30 '16 at 20:41
add a comment |
On my systemsystem-authdid not exist; it was/etc/common-auth. Thanks!
– Luc
Jul 30 '16 at 20:41
On my system
system-auth did not exist; it was /etc/common-auth. Thanks!– Luc
Jul 30 '16 at 20:41
On my system
system-auth did not exist; it was /etc/common-auth. Thanks!– Luc
Jul 30 '16 at 20:41
add a comment |
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1
I get the need for a delay from a security perspective, but the default delay is rather annoying
– Mike Pennington
Jun 16 '12 at 21:41
3
This has been interesting; maybe I'll write a module that allows N tries with no delay followed by any number of tries with a long delay.
– Shawn J. Goff
Jun 16 '12 at 23:27
1
Instead of a new module (suggested in my previous comment), I used
pam_unixwith thenodelayoption andpam_tally2withdeny=5 unlock_time=15; this allows for 5 immediate retries, but denies access (even with a successful password) for 15 seconds. I still intend to try writing the described model, but now it's a back-burner project, because this would not be suitable if your primary access to the system is network-based since it makes a DOS attack trivial.– Shawn J. Goff
Jun 20 '12 at 22:25
1
if you are concerned about a network DoS from timeouts, use fail2ban... in fact use it even if you think you're safe :-). i use two day ban times
– Mike Pennington
Jun 20 '12 at 23:18