Nagios monitoring system memory

Linux memory mechanism: in linux, there is such an idea that the memory does not need to be white, so it tries its best to cache and buffer some data to facilitate the next use. But in fact, these memories can also be used immediately. So the idle memory free + buffers + cachedcheck_mem.sh monitoring script is found online.

Linux memory mechanism: in linux, there is such an idea that the memory does not need to be white, so it tries its best to cache and buffer some data to facilitate the next use. But in fact, these memories can also be used immediately. So idle memory =Free+ Buffers + cachEd

Check_mem.sh this monitoring script was found online. the obtained memory value is the three Mem: total userd free values from free-m. according to the above statement. this monitoring method is incorrect. so I modified the script. very simple. these two values are modified:

1. # Total memory uSed
2. Used = 'free-m | head-3 | tail-1 | awk '{print $3 }''
3. # Calc total minus used
4. Free = 'free-m | head-3 | tail-1 | awk '{print $4 }''

Check_mem.sh

1. #! /Bin/bash
2. USAGE = "'basename $ 0' [-w | -- warning] [-C | -- critical] "
3. THRESHOLD_USAGE = "WARNING threshold must be greater than CRITICAL: 'basename $ 0' $ *"
4. Calc =/tmp/meMcC
5. Percent_free =/tmp/mempercent
6. Critical = ""
7. Warning = ""
8. STATE_ OK = 0
9. STATE_WARNING = 1
10. STATE_CRITICAL = 2
11. STATE_UNKNOWN = 3
12. # Print usage
13. If [[$ #-lt 4]
14. Then
15. Echo ""
16. Echo "Wrong Syntax: 'basename $ 0' $ *"
17. Echo ""
18. Echo "Usage: $ USAGE"
19. Echo ""
20. ExIt 0
21. Fi
22. # Read input
23. While [[$ #-gt 0]
24. Do
25. Case "$1" in
26. -W | -- warning)
27. Shift
28. Warning = $1
29. ;;
30. -C | -- critical)
31. Shift
32. Critical = $1
33. ;;
34. Esac
35. Shift
36. Done
39. # Verify input
40. If [[$ warning-eq $ critical | $ warning-lt $ critical]
41. Then
42. Echo ""
43. Echo "$ THRESHOLD_USAGE"
44. Echo ""
45. Echo "Usage: $ USAGE"
46. Echo ""
47. Exit 0
48. Fi
49. # Total memory available
50. Total = 'free-m | head-2 | tail-1 | gawk '{print $2 }''
51. # Total memory used
52. Used = 'free-m | head-3 | tail-1 | awk '{print $3 }''
53. # Calc total minus used
54. Free = 'free-m | head-3 | tail-1 | awk '{print $4 }''
55. # NoRmAl values
56. # Echo "$ total" MB total
57. # Echo "$ used" MB used
58. # Echo "$ free" MB free
59. # Make it into % percent free = (free mem/total mem) * 100)
60. Echo "5"> $ calc # decimal accuracy
61. Echo "k"> $ calc # commit
62. Echo "100"> $ calc # multiply
63. Echo "$ free"> $ calc # division integer
64. Echo "$ total"> $ calc # division integer
65. Echo "/"> $ calc # division sign
66. Echo "*"> $ calc # multipliCatIon sign
67. Echo "p"> $ calc # print
68. Percent = '/usr/bin/dc $ calc |/bin/sed's/^ \./0./' |/usr/bin/Tr"." "|/Usr/bin/gawk {'print $1 '}'
69. # Percent1 = '/usr/bin/dc $ calc'
70. # Echo "$ percent1"
71. If [["$ percent"-le $ critical]
72. Then
73. Echo "CRITICAL-$ free MB ($ percent %) Free Memory"
74. Exit 2
75. Fi
76. If [["$ percent"-le $ warning]
77. Then
78. Echo "WARNING-$ free MB ($ percent %) Free Memory"
79. Exit 1
80. Fi
81. If [["$ percent"-gt $ warning]
82. Then
83. Echo "OK-$ free MB ($ percent %) Free Memory"
84. Exit 0
85. Fi