Log file timestamp

J_Davis · June 18, 2008, 8:22pm

Hello,

I’m trying to figure out why my nginx access log timestamps are an hour
behind the actual time.
I’ve confirmed that the “date” and “hwclock” commands both return the
proper
values on the system and that the timezone is correct but the timestamps
in
the nginx logs are all an hour off.
I realize this may not be an Nginx problem but I’m not sure how else to
narrow down the possibilities.

Any insights are greatly appreciated.

RedHat el5 - 2.6.18-8.el5
nginx/0.6.29

Thanks,
-Jake

J_Davis · June 18, 2008, 9:07pm

On Wed, Jun 18, 2008 at 02:10:37PM -0400, J Davis wrote:

RedHat el5 - 2.6.18-8.el5
nginx/0.6.29

This may be incorrectly set daylight saving time offset.
Could you show last line from access log and output of

date

and

date -u

?

J_Davis · June 18, 2008, 9:59pm

I think you are on to something.

date: Wed Jun 18 15:23:03 EDT 2008
date -u: Wed Jun 18 19:23:05 UTC 2008
access.log: 18/Jun/2008:14:23:34 -0500

I made sure that my tzdata package was up to date and that
/etc/localtime
points to the correct zone at /usr/share/zoneinfo/America/New_York. I
then
gave nginx the HUP signal (not sure if that was necessary).

but the time stamps are still 1 hour behind.

-Jake

J_Davis · June 18, 2008, 11:02pm

On Wed, Jun 18, 2008 at 03:51:37PM -0400, J Davis wrote:

but the time stamps are still 1 hour behind.
Could you build the program below and run it together with date and date
-u ?

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include <time.h>
#include <stdio.h>

int
main()
{
time_t s;
struct tm t;

tzset();

s = time(NULL);

(void) localtime_r(&s, &t);

printf("%02d:%02d %d %d\n", t.tm_hour, t.tm_min, t.tm_isdst,

timezone);

return 0;

}

Also could you send the output of nginx’s ./configure ?

J_Davis · June 19, 2008, 2:21pm

Forgot this part…

./configure
checking for OS

Linux 2.6.18-8.el5 x86_64
checking for C compiler … found
using GNU C compiler
gcc version: 4.1.2 20070626 (Red Hat 4.1.2-14)
checking for gcc -pipe switch … found
checking for gcc variadic macros … found
checking for C99 variadic macros … found
checking for unistd.h … found
checking for inttypes.h … found
checking for limits.h … found
checking for sys/filio.h … not found
checking for crypt.h … found
checking for malloc.h … found
checking for Linux specific features
checking for epoll … found
checking for sendfile() … found
checking for sendfile64() … found
checking for sys/prctl.h … found
checking for prctl(PR_SET_DUMPABLE) … found
checking for sched_setaffinity() … found
checking for nobody group … found
checking for poll() … found
checking for /dev/poll … not found
checking for kqueue … not found
checking for crypt() … not found
checking for crypt() in libcrypt … found
checking for PCRE library … found
checking for zlib library … found
checking for int size … 4 bytes
checking for long size … 8 bytes
checking for long long size … 8 bytes
checking for void * size … 8 bytes
checking for uint64_t … found
checking for sig_atomic_t … found
checking for sig_atomic_t size … 4 bytes
checking for socklen_t … found
checking for in_addr_t … found
checking for in_port_t … found
checking for rlim_t … found
checking for uintptr_t … uintptr_t found
checking for system endianess … little endianess
checking for size_t size … 8 bytes
checking for off_t size … 8 bytes
checking for time_t size … 8 bytes
checking for setproctitle() … not found
checking for pread() … found
checking for pwrite() … found
checking for strerror_r() … found but is not working
checking for gnu style strerror_r() … found
checking for localtime_r() … found
checking for posix_memalign() … found
checking for memalign() … found
checking for sched_yield() … found
checking for mmap(MAP_ANON|MAP_SHARED) … found
checking for mmap("/dev/zero", MAP_SHARED) … found
checking for System V shared memory … found
checking for struct msghdr.msg_control … found
checking for ioctl(FIONBIO) … found
checking for struct tm.tm_gmtoff … found

Configuration summary

threads are not used
using system PCRE library
OpenSSL library is not used
md5 library is not used
sha1 library is not used
using system zlib library

nginx path prefix: “/usr/local/nginx”
nginx binary file: “/usr/local/nginx/sbin/nginx”
nginx configuration prefix: “/usr/local/nginx/conf”
nginx configuration file: “/usr/local/nginx/conf/nginx.conf”
nginx pid file: “/usr/local/nginx/logs/nginx.pid”
nginx error log file: “/usr/local/nginx/logs/error.log”
nginx http access log file: “/usr/local/nginx/logs/access.log”
nginx http client request body temporary files:
“/usr/local/nginx/client_body_temp”
nginx http proxy temporary files: “/usr/local/nginx/proxy_temp”
nginx http fastcgi temporary files: “/usr/local/nginx/fastcgi_temp”

Thanks!

J_Davis · June 19, 2008, 2:17pm

here’s the output…
07:58 1 18000
date: Thu Jun 19 07:58:26 EDT 2008
date -u: Thu Jun 19 11:58:27 UTC 2008

-Jake

J_Davis · June 19, 2008, 3:03pm

On Thu, Jun 19, 2008 at 08:08:32AM -0400, J Davis wrote:

checking for struct tm.tm_gmtoff … found

Well, could you built a new program below and run it with date’s again ?

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include <time.h>
#include <stdio.h>

int
main()
{
time_t s;
struct tm t;

tzset();

s = time(NULL);

(void) localtime_r(&s, &t);

printf("%02d:%02d %d %d\n", t.tm_hour, t.tm_min, t.tm_isdst,

t.tm_gmtoff);

return 0;

}

J_Davis · June 19, 2008, 3:42pm

On Thu, Jun 19, 2008 at 09:08:07AM -0400, J Davis wrote:

09:07 1 -14400
date: Thu Jun 19 09:07:04 EDT 2008
date -u: Thu Jun 19 13:07:06 UTC 2008

Now it shows correct time.
Could you make nginx dummy online upgrade ?

kill -USR2 cat nginx.pid
sleep 3
kill -QUIT cat nginx.pid.oldbin

nginx calls tzset() in master process on start only.
Probably your timezone setting was incorrect before.

J_Davis · June 19, 2008, 3:21pm

09:07 1 -14400
date: Thu Jun 19 09:07:04 EDT 2008
date -u: Thu Jun 19 13:07:06 UTC 2008

-Jake

J_Davis · June 19, 2008, 5:32pm

For some reason I get this in the error log when giving nginx the -USR2
sginal.

2008/06/19 08:50:31 [crit] 32282#0: the changing binary signal is
ignored:
you should shutdown or terminate before either old or new binary’s
process

J_Davis · June 19, 2008, 5:55pm

On Thu, Jun 19, 2008 at 09:53:20AM -0400, J Davis wrote:

For some reason I get this in the error log when giving nginx the -USR2
sginal.

2008/06/19 08:50:31 [crit] 32282#0: the changing binary signal is ignored:
you should shutdown or terminate before either old or new binary’s process

If you never did online upgrade before, this may mean that you run nginx
under daemontools/etc. Thus online upgrade is not available in this
case.

J_Davis · June 19, 2008, 6:46pm

That was it exactly. Times are correct now.
Thank you very much for the assistance.

-Jake