monitor snmpd - problems with option -e

[Lentes, Bernd]

Hi,

this is my fourth effort to write an e-Mail to this list.

i'd like to investigate the snmpd, especially from where it gets its data.
I think one source are named pipes.
lsof tells me:

snmpd   3912 root    4r     FIFO   0,10      0t0   26953 pipe
snmpd   3912 root    5w     FIFO   0,10      0t0   26953 pipe

I'd like to see the data which flows through the pipes.
So i thouhgt this commandline would helpe me:
strace -p 3912 -e read=4,5

According to the manpage this should print the data read from these two filedescriptors:
-e read=set Perform a full hexadecimal and ASCII dump of all the data read from file descriptors listed in the specified set.  For example, to see all input  activity  on
file  descriptors 3 and 5 use -e read=3,5.  Note that this is independent from the normal tracing of the read(2) system call which is controlled by the option
-e trace=read.

But it doesn't. I get tons of lines with enourmous information, much more than i want:
 ...
close(13)                               = 0
munmap(0x7fb594631000, 4096)            = 0
open("/proc/sys/net/ipv6/neigh/vnet1/base_reachable_time_ms", O_RDONLY) = 13
fstat(13, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fb594631000
read(13, "30000\n", 1024)               = 6
close(13)                               = 0
munmap(0x7fb594631000, 4096)            = 0
socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 13
ioctl(13, SIOCGIFINDEX, {ifr_name="eth0", ifr_index=2}) = 0
close(13)                               = 0
ioctl(12, SIOCGIFCONF, {120, {{"\2", {AF_INET, inet_addr("127.0.0.1")}}, {"\2", {AF_INET, inet_addr("192.168.100.10")}}, {"\2", {AF_INET, inet_addr("146.107.235.13")}}}}) = 0
ioctl(12, SIOCGIFCONF, {120, {{"\2", {AF_INET, inet_addr("127.0.0.1")}}, {"\2", {AF_INET, inet_addr("192.168.100.10")}}, {"\2", {AF_INET, inet_addr("146.107.235.13")}}}}) = 0
socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 13
ioctl(13, SIOCGIFINDEX, {ifr_name="eth0", ifr_index=2}) = 0
close(13)                               = 0
ioctl(12, SIOCGIFHWADDR, {ifr_name="eth0", ifr_hwaddr=70:10:6f:b8:dc:00}) = 0
ioctl(12, SIOCETHTOOL, 0x7ffca91aa9b0)  = 0
ioctl(12, SIOCGIFFLAGS, {ifr_name="eth0", ifr_flags=IFF_UP|IFF_BROADCAST|IFF_RUNNING|IFF_SLAVE|IFF_MULTICAST}) = 0
ioctl(12, SIOCGIFMTU, {ifr_name="eth0", ifr_mtu=1500}) = 0
read(11, "", 1024)                      = 0
close(11)                               = 0
munmap(0x7fb594633000, 4096)            = 0
close(12)                               = 0
select(11, [4 6 7 8 9 10], [], [], {0, 227352}) = 0 (Timeout)
open("/proc/diskstats", O_RDONLY)       = 11
fstat(11, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fb594633000
read(11, "   8       0 sda 71765 0 1772604"..., 1024) = 1024
read(11, "124 0 2752 496 0 0 0 0 0 496 496"..., 1024) = 690

Where is the error in my commandline ? Can someone sort out this ?
I have SLES 12 SP3, strace 4.10-3.1.

Thanks.


Bernd 


-- 

Bernd Lentes 
Systemadministration 
Institut für Entwicklungsgenetik 
Gebäude 35.34 - Raum 208 
HelmholtzZentrum münchen 
[ mailto:bernd.lentes at helmholtz-muenchen.de | bernd.lentes at helmholtz-muenchen.de ] 
phone: +49 89 3187 1241 
fax: +49 89 3187 2294 
[ http://www.helmholtz-muenchen.de/idg | http://www.helmholtz-muenchen.de/idg ] 

wer Fehler macht kann etwas lernen 
wer nichts macht kann auch nichts lernen
 

Helmholtz Zentrum Muenchen
Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH)
Ingolstaedter Landstr. 1
85764 Neuherberg
www.helmholtz-muenchen.de
Aufsichtsratsvorsitzende: MinDirig'in Petra Steiner-Hoffmann
Stellv.Aufsichtsratsvorsitzender: MinDirig. Dr. Manfred Wolter
Geschaeftsfuehrer: Prof. Dr. med. Dr. h.c. Matthias Tschoep, Heinrich Bassler, Dr. rer. nat. Alfons Enhsen
Registergericht: Amtsgericht Muenchen HRB 6466
USt-IdNr: DE 129521671