[rrd-developers] MRTG , Segmentation Fault , After re-installing perl .

[Mr. James W. Laferriere]

  	Hello Kevin ,

On Thu, 12 Mar 2009, kevin brintnall wrote:
> On Thu, Mar 12, 2009 at 10:43:16AM -0800, Mr. James W. Laferriere wrote:
>>
>>  	CFLAGS=-g ./configure ; CFLAGS=-g make ; CFLAGS=-g make install
>
>> The above shows that either I have not configured & made rrdtool with
>> debugging or there is no write_RRA_row() available .  I suspect the
>> former .
>
> The call to write_RRA_row() is probably being optimized out.  However, we
> may be able to get the info we need now that the symbols are available.
>
>> #3  0xb7d5f2ac in sprintf_alloc (fmt=0xb7d6b5c2 "[%lli]RRA[%s][%lu]DS[%s]") at rrd_info.c:34
>> #4  0xb7d64193 in write_to_rras (rrd=0xbfd57f94, rrd_file=0x89cd7d8, rra_step_cnt=<value optimized out>, rra_begin=2760,
>>      current_time=1236882919, skip_update=0x89cd838, pcdp_summary=0xbfd57ff0) at rrd_update.c:1944
>
> Try this:
>
>  (gdb) select 4
>  (gdb) p *rrd
>  (gdb) p rra_idx
>  (gdb) p rrd->rra_def[rrd_idx]
>  (gdb) p rrd->rra_def[rrd_idx].cf_nam
>  (gdb) p rrd->rra_def[rra_idx].pdp_cnt
>  (gdb) p ds_idx
>  (gdb) p rrd->ds_def[ds_idx].ds_nam
>
> Also, I have a few other questions:
>
> - is it always the same RRD file that causes the crash?
 	No ,  All .cfg files caused SegFaults .

> - does that RRD cause the crash every time?
 	Yes ,  every time .

> - do you have any similar files (i.e. same RRA and DS definitions) that
>  do not cause crash?
 	Not that I know of ,  as I said above any mrtg .cfg file causes a 
Segfault .

 	Below is the output from above you requested .
 		Tnx ,  JimL

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This GDB was configured as "i486-slackware-linux"...
Using host libthread_db library "/lib/libthread_db.so.1".
(gdb) set args /usr/local/mrtg-2/bin/mrtg-ORIG /var/www/htdocs/router2cgi/cfg/to-rtr01.cfg
(gdb) run
Starting program: /usr/local/bin/perl /usr/local/mrtg-2/bin/mrtg-ORIG /var/www/htdocs/router2cgi/cfg/to-rtr01.cfg
[Thread debugging using libthread_db enabled]
[New Thread -1210005824 (LWP 7677)]
Error while reading shared library symbols:
Cannot find new threads: generic error

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1210005824 (LWP 7677)]
0xb7e7b22b in strlen () from /lib/libc.so.6
(gdb) bt
#0  0xb7e7b22b in strlen () from /lib/libc.so.6
#1  0xb7e4d281 in vfprintf () from /lib/libc.so.6
#2  0xb7e6bd91 in vsnprintf () from /lib/libc.so.6
#3  0xb7d982ac in sprintf_alloc (fmt=0xb7da45c2 "[%lli]RRA[%s][%lu]DS[%s]") at rrd_info.c:34
#4  0xb7d9d193 in write_to_rras (rrd=0xbfa6fca4, rrd_file=0x8855f18, rra_step_cnt=<value optimized out>, rra_begin=2760,
     current_time=1236895229, skip_update=0x89cdf08, pcdp_summary=0xbfa6fd00) at rrd_update.c:1944
#5  0xb7d9dd1f in process_arg (step_start=0x89c47b8 "1236895229", rrd=0xbfa6fca4, rrd_file=0x8855f18, rra_begin=81864,
     current_time=0xbfa6fcd8, current_time_usec=0xbfa6fcd4, pdp_temp=0x897ad60, pdp_new=0x897ad78, rra_step_cnt=0x897b258,
     updvals=0x88878f0, tmpl_idx=0x8888fc0, tmpl_cnt=3, pcdp_summary=0xbfa6fd00, version=3, skip_update=0x89cdf08,
     schedule_smooth=0xbfa6fcd0) at rrd_update.c:819
#6  0xb7d9ee8a in _rrd_update (filename=0x89cdf70 "/var/www/htdocs/router2cgi/graphs/to-rtr01/to-rtr01_1.rrd", tmplt=0x0, argc=1,
     argv=0x885f7c0, pcdp_summary=0x88795e0) at rrd_update.c:497
#7  0xb7d9f4a1 in rrd_update_v (argc=2, argv=0x885f7b8) at rrd_update.c:362
#8  0xb7dac0cf in XS_RRDs_updatev () from /usr/local/lib/perl5/site_perl/5.10.0/i686-linux//auto/RRDs/RRDs.so
#9  0x0809ed60 in Perl_pp_entersub ()
#10 0x0809d638 in Perl_runops_standard ()
#11 0x08099fa4 in perl_run ()
#12 0x0805ed7f in main ()
(gdb)  select 4
(gdb) p *rrd
$1 = {stat_head = 0xb7d61000, ds_def = 0xb7d61070, rra_def = 0xb7d61160, live_head = 0xb7d614c0, legacy_last_up = 0x0,
   pdp_prep = 0xb7d614c8, cdp_prep = 0xb7d615a8, rra_ptr = 0xb7d61aa8, rrd_value = 0x0}
(gdb) p rra_idx
$2 = 0
(gdb) p rrd->rra_def[rrd_idx]
No symbol "rrd_idx" in current context.
(gdb) p rrd->rra_def[rrd_idx][1 at a
$3 = {cf_nam = "AVERAGE", '\0' <repeats 12 times>, row_cnt = 599, pdp_cnt = 1, par = {{u_cnt = 0, u_val = 0.5}, {u_cnt = 0,
       u_val = 0}, {u_cnt = 0, u_val = 0}, {u_cnt = 0, u_val = 0}, {u_cnt = 0, u_val = 0}, {u_cnt = 0, u_val = 0}, {u_cnt = 0,
       u_val = 0}, {u_cnt = 0, u_val = 0}, {u_cnt = 0, u_val = 0}, {u_cnt = 0, u_val = 0}}}
(gdb) p rrd->rra_def[rra_idx].cf_nam
$4 = "AVERAGE", '\0' <repeats 12 times>
(gdb) p rrd->rra_def[rra_idx].cf_nam      pdp_cnt
$5 = 1
(gdb) p ds_idx
No symbol "ds_idx" in current context.
(gdb) p ds_idxrrd->rra_def[rra_idx].pdp_cntcf_nam[1 at d[1 at sra[1 at d[1 at s
No symbol "ds_idx" in current context.
(gdb) p rrd->rra_def[ds_idx].ds_nam[1 at d[1 at s
No symbol "ds_idx" in current context.
(gdb) 
No symbol "ds_idx" in current context.
(gdb) 
No symbol "ds_idx" in current context.
(gdb) quit
The program is running.  Exit anyway? (y or n)


-- 
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| James   W.   Laferriere | System    Techniques | Give me VMS     |
| Network&System Engineer | 2133    McCullam Ave |  Give me Linux  |
| babydr at baby-dragons.com | Fairbanks, AK. 99701 |   only  on  AXP |
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