linux_maintenance_tracing

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linux_maintenance_tracing [2019/10/18 20:04] – external edit 127.0.0.1linux_maintenance_tracing [2020/05/01 14:16] (current) – andonovj
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-====Locate a session==== 
-First thing is to locate the session PID, in our example we want to monitor a NAGIOS client, therefore we have to minitor a process called: "xinet" which is a parent to the nagios: 
  
-<sxh bash> 
-[root@oraback libexec]# ps -leaf | grep -i xinet 
-0 S root      4622 31523  0  78   0 - 15298 pipe_w 10:33 pts/0    00:00:00 grep -i xinet 
-1 S root      6177     1  0  75   0 -  5416 -      Jan19 ?        00:00:16 xinetd -stayalive -pidfile /var/run/xinetd.pid 
-</sxh> 
- 
- 
-====Trace==== 
-Once we have located the parent process, we can start tracing: 
- 
- 
-<sxh bash> 
-[root@oraback libexec]# strace -o /tmp/x -fp 6177 
-Process 6177 attached - interrupt to quit 
-Process 4644 attached (waiting for parent) 
-Process 4644 resumed (parent 6177 ready) 
-Process 4645 attached (waiting for parent) 
-Process 4645 resumed (parent 4644 ready) 
-Process 4644 suspended 
-Process 4646 attached (waiting for parent) 
-Process 4646 resumed (parent 4645 ready) 
-Process 4647 attached (waiting for parent) 
-</sxh> 
- 
-This command, will trace all info, into a file called: /tmp/x 
- 
-====Verbose==== 
-In case of need, the trace can be extended to include more data using: 
- 
- 
-<sxh bash> 
-[root@oraback libexec]# strace -vo /tmp/x -fp 6177 
-Process 6177 attached - interrupt to quit 
-Process 5089 attached (waiting for parent) 
-Process 5089 resumed (parent 6177 ready) 
-Process 5091 attached (waiting for parent) 
-Process 5091 resumed (parent 5089 ready) 
-Process 5089 suspended 
-Process 5093 attached (waiting for parent) 
-Process 5093 resumed (parent 5091 ready) 
-Process 5093 detached 
-Process 5089 resumed 
-Process 5091 detached 
-</sxh> 
- 
-After that we can examine the content of a trace file: 
- 
- 
-<sxh bash> 
-[root@oraback libexec]# less /tmp/x 
-2280  <... nanosleep resumed> NULL)     = 0 
-2280  nanosleep({1, 0},  <unfinished ...> 
-2286  <... futex resumed> )             = -1 ETIMEDOUT (Connection timed out) 
-2286  futex(0x38891f8, FUTEX_WAKE_PRIVATE, 1) = 0 
-2286  futex(0x3889224, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 161, {1528735731, 389058000}, ffffffff <unfinished ...> 
-2287  <... futex resumed> )             = -1 ETIMEDOUT (Connection timed out) 
-2279  <... futex resumed> )             = -1 ETIMEDOUT (Connection timed out) 
-2287  futex(0x38d5658, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 
-2279  futex(0x31f49f8, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 
-2287  <... futex resumed> )             = 0 
-2279  <... futex resumed> )             = 0 
-2287  futex(0x38d5684, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 319, {1528735726, 392983000}, ffffffff <unfinished ...> 
-2279  futex(0x31f4a24, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 319, {1528735726, 392985000}, ffffffff <unfinished ...> 
-2278  <... futex resumed> )             = -1 ETIMEDOUT (Connection timed out) 
-2277  <... futex resumed> )             = -1 ETIMEDOUT (Connection timed out) 
-2275  <... futex resumed> )             = -1 ETIMEDOUT (Connection timed out) 
-2278  futex(0x31f4968, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 
-2277  futex(0x3884a78, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 
-2275  futex(0x31f4b18, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 
-2278  <... futex resumed> )             = 0 
-2277  <... futex resumed> )             = 0 
-2275  <... futex resumed> )             = 0 
-2278  futex(0x31f4994, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 1589, {1528735722, 422523000}, ffffffff <unfinished ...> 
-2277  futex(0x3884aa4, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 1589, {1528735722, 422489000}, ffffffff <unfinished ...> 
-</sxh> 
  • linux_maintenance_tracing.1571429096.txt.gz
  • Last modified: 2019/10/18 20:04
  • by 127.0.0.1