Get all the values for a single index in snmp - snmp

I amb reading the snmp values for a qnap nas, I have three storage with different metrics I'd like to collect, I would like to have a command to get all the values for index=1, but so far I haven't find any snmp command to accomplish it.
volumeID.1 = INTEGER: 1
volumeID.2 = INTEGER: 2
volumeID.3 = INTEGER: 3
volumeCapacity.1 = Counter64: 8716194508
volumeCapacity.2 = Counter64: 8716194508
volumeCapacity.3 = Counter64: 8716194508
volumeFreeSize.1 = Counter64: 3995664864
volumeFreeSize.2 = Counter64: 2783145980
volumeFreeSize.3 = Counter64: 1360632936
volumeStatus.1 = STRING: "Ready"
volumeStatus.2 = STRING: "Ready"
volumeStatus.3 = STRING: "Ready"
volumeSSDCache.1 = INTEGER: -1
volumeSSDCache.2 = INTEGER: -1
volumeSSDCache.3 = INTEGER: -1
I used the command below to get the output shown, but it only reads sequentialy the values I request.
snmpbulkget -m All -v2c -Cn0 -Cr15 -Os -c public nas NAS-MIB::volumeID
This would be also useful for any non-table indexed values

While row-traversal (through the indices) is easy, you have to collect the columns (objects) explicitely, eg.
snmpget ... volumeID.1 volumeCapacity.1 volumeFreeSize.1 ...
(and yes, you can skip the INDEX object volumeID because it's value is just it's index).

Related

Change or personalize OID

Finally managed to have my RPI computer module to work with SNMP.
I have a script running that gives me one of my parameters and if I use query using SNMP I get the info back.
pi#raspberrypi:~ $ snmpwalk -v2c -c public localhost NET-SNMP-EXTEND-MIB::nsExtendObjects | grep snmp_status
NET-SNMP-EXTEND-MIB::nsExtendCommand."snmp_status" = STRING: /home/pi/BDC/snmp_status.py
NET-SNMP-EXTEND-MIB::nsExtendArgs."snmp_status" = STRING:
NET-SNMP-EXTEND-MIB::nsExtendInput."snmp_status" = STRING:
NET-SNMP-EXTEND-MIB::nsExtendCacheTime."snmp_status" = INTEGER: 5
NET-SNMP-EXTEND-MIB::nsExtendExecType."snmp_status" = INTEGER: exec(1)
NET-SNMP-EXTEND-MIB::nsExtendRunType."snmp_status" = INTEGER: run-on-read(1)
NET-SNMP-EXTEND-MIB::nsExtendStorage."snmp_status" = INTEGER: permanent(4)
NET-SNMP-EXTEND-MIB::nsExtendStatus."snmp_status" = INTEGER: active(1)
NET-SNMP-EXTEND-MIB::nsExtendOutput1Line."snmp_status" = STRING: 0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."snmp_status" = STRING: 0
NET-SNMP-EXTEND-MIB::nsExtendOutNumLines."snmp_status" = INTEGER: 1
NET-SNMP-EXTEND-MIB::nsExtendResult."snmp_status" = INTEGER: 0
NET-SNMP-EXTEND-MIB::nsExtendOutLine."snmp_status".1 = STRING: 0
If my unit is in alarm replies with
NET-SNMP-EXTEND-MIB::nsExtendOutLine."snmp_status".1 = STRING: 1
if not in alarm replies with
NET-SNMP-EXTEND-MIB::nsExtendOutLine."snmp_status".1 = STRING: 0
This status is stored in a file and it's parsed to the SNMP using a python script.
Now... next question.
The SNMP server gives me the following OID
.1.3.6.1.4.1.8072.1.3.2.3.1.2.11.115.110.109.112.95.115.116.97.116.117.115
and for each parameter it gives me one very different IOD.
How can I change this for something more easy... like the ones we see on MIB files?
If you are doing it in the command line, use
snmptranslate -m NET-SNMP-EXTEND-MIB .1.3.6.1.4.1.8072.1.3.2.3.1.2.11.115.110.109.112.95.115.116.97.116.117.115
To do it purely programmatically (i.e. without parsing command line output), you will need a way to parse the MIB files. I think such tools probably exist in Python, but I've never used them myself.
More often, I hard-code constants for the OIDs that I'm interested in, and manually inspect the MIB to know how to decode the index for each object. The OID you gave is an instance of NET-SNMP-EXTEND-MIB::nsExtendOutputFull, which belongs to nsExtendOutput1Entry. Normally the *Entry types will have an INDEX field telling you which field is used as the index of that table. In this case, it has an AUGMENTS field instead, which points you to nsExtendConfigEntry. The INDEX fornsExtendConfigEntry is nsExtendToken, which has a type of DisplayString (basically an OCTET STRING that is limited to human-readable characters).
Here's an example of how I would do this in Python -- you'll need pip install snmp:
from snmp.types import OID, OctetString
nsExtendOutputFull = OID.parse(".1.3.6.1.4.1.8072.1.3.2.3.1.2")
oid = OID.parse(".1.3.6.1.4.1.8072.1.3.2.3.1.2.11.115.110.109.112.95.115.116.97.116.117.115")
nsExtendToken = oid.extractIndex(nsExtendOutputFull, OctetString)
print(f"Index = {nsExtendToken}")
Here's the output:
Index = OctetString(b'snmp_status')

Omnetpp.ini - How to create loop for the host parametres

I have 1000 hosts. I need to simulate the situation when host[0] connects with other 999 hosts by PingApp in accordance with a timetable.
For example
**.host[0]*.numPingApps = 999 #number of hosts
**.host[0]*.pingApp[*].typename = "PingApp"
**.host[0]*.pingApp[*].packetSize = 42 B
**.host[0]*.pingApp[*].sendInterval = 1 s
**.host[0]*.pingApp[*].srcAddr = "host[0]"
**.host[0]*.pingApp[0].destAddr = "host[1]"
**.host[0]*.pingApp[0].startTime = 0 s
**.host[0]*.pingApp[0].stopTime = 5s
**.host[0]*.pingApp[1].destAddr = "host[2]"
**.host[0]*.pingApp[1].startTime = 0.1 s
**.host[0]*.pingApp[1].stopTime = 5.1 s
**.host[0]*.pingApp[2].destAddr = "host[3]"
**.host[0]*.pingApp[2].startTime = 0.2 s
**.host[0]*.pingApp[2].stopTime = 5.2 s
**.host[0]*.pingApp[3].destAddr = "host[4]"
**.host[0]*.pingApp[3].startTime = 0.3 s
**.host[0]*.pingApp[3].stopTime = 5.3 s
and so on...
How can I create the loop for automatic changes of parameters: startTime, stopTime, destAddr, number of pingApp?
I need to increase startTime and stopTime by 0.1s at every step of one point increase of pingApp number and destAddr.
Help me please!
Thank you!
Actually, every host should have only one Ping Application. To achieve your goal you can use the following settings:
**.host[*].numApps = 1
**.host[*].app[0].typename = "PingApp"
**.host[999].app[0].destAddr = "host[0]"
**.host[*].app[0].destAddr = "host[" + string(parentIndex()+1) + "]"
**.host[*].app[0].startTime = replaceUnit (0.1*(parentIndex()), "s")
**.host[*].app[0].stopTime = replaceUnit (5 + 0.1*(parentIndex()), "s")
The paretnIndex() returns the index of the host in vector of hosts, reference OMNeT++ Manual. For the last node (i.e. host[999]) destAddr is set by hand because parentIndex()+1 will return 1000, and there is no host[1000].
The second NED function - replaceUnit() - is used to add the unit to the result of calculation.
Here is an other quasi solution:
From the PingApp's documentation:
string destAddr = default(""); // destination address(es), separated by spaces, "*" means all IPv4/IPv6 interfaces in entire simulation
Specifying '*' allows pinging ALL configured network interfaces in the
whole simulation. This is useful to check if a host can reach ALL other
hosts in the network (i.e. routing tables were set up properly).
To specify the number of ping requests sent to a single destination address,
use the 'count' parameter. After the specified number of ping requests was
sent to a destination address, the application goes to sleep for 'sleepDuration'.
Once the sleep timer has expired, the application switches to the next destination
and starts pinging again. The application stops pinging once all destination
addresses were tested or the simulation time reaches 'stopTime'.
So if you have only these hosts in the network and you don't mind that in the beginning the host pings itself too, destAddr="*" and count=1
I combined answers of #Rudi and #JerzyD. and got the workable solution:
**.host[0]*.numPingApps = 999
**.host[0]*.pingApp[*].typename = "PingApp"
**.host[0]*.pingApp[*].sendInterval = 1 s
**.host[0]*.pingApp[*].packetSize = 42 B
**.host[0]*.pingApp[0..998].destAddr = "host[" + string(index()+1) + "]"
**.host[0]*.pingApp[0..998].startTime = replaceUnit (0.1 * (index()), "s")
**.host[0]*.pingApp[0..998].stopTime = replaceUnit (5 + 0.1 * (index()), "s")

How to LM Hash in Powershell

OK so i have been working on this for a bit, and i cant see how to get any further. I keep running into roadblocks with the DESCryptoServiceProvider and somehow it just doesnt seem to be comming out with the right answers.
the sudo code version of LM_Hash is:
LMHASH = concat(DES(Upper(PWD)[0..7],KGS!##$%),DES(Upper(PWD)[8..13],KGS!##$%))
First issue is the LM Key I keep seeing the atleast two variants its either "KGS!##$%" or "KGS!+#$%" neither gets me the right answers but both dont seem to fit with the origin story (its KGS and SHIFT 12345 assuming a US keyboard
on a UK thats "KGS!"£$%")
I am pretty sure i have the parameters set up correctly now, but my understanding seems to be failing me. here's what i have so far, any help is appreciated I am running Powershell V5.1 on Win 10, the string to encrypt is passed in as $string
$plaintext = "KGS!##$%"
$OEM = [System.Text.Encoding]::GetEncoding($Host.CurrentCulture.TextInfo.OEMCodePage)
$str1 = $OEM.GetBytes($string.substring(0,7)) +[Byte]$null
$str2 = $OEM.GetBytes($string.Substring(7)) +[Byte]$null
$IV = new-object "System.Byte[]" 8
$hasher = New-Object -TypeName System.Security.Cryptography.DESCryptoServiceProvider -Property #{key=$str1; IV = $IV; mode = [System.Security.Cryptography.CipherMode]::ECB; Padding=[System.Security.Cryptography.PaddingMode]::None}
$outbyte = new-object "System.Byte[]" 8
$encrypter1 = $hasher.CreateEncryptor()
$outbyte = $encrypter1.TransformFinalBlock($OEM.GetBytes($plaintext),0,8)
$data1 = [System.BitConverter]::ToString($outbyte).replace("-","")
$encrypter1.Dispose()
In theory this should encrypt the Key (which ever one it is) with DES using the first 7 characters of the string ($str1) as the key (with a null byte on the end) and then we do this to the second half ($str2) and concat them back together to get the LMHASH.
The ASCII-encoded string KGS!##$% is the correct magic constant to use
using the first 7 characters of the string ($str1) as the key (with a null byte on the end)
This, however, is incorrect. The key is not composed by padding the 7 bytes of partial input with a single 0-byte at the end, but by partitioning the input into 8 7-bit chunks and left-shifting them once (resulting in 8 bytes).
The easiest way to implement this in PowerShell is probably with strings, so I'd likely do something like this:
# Convert string to byte array
$inBytes = $OEM.GetBytes($str1)
# Create a binary string from our bytes
$bitString = ''
foreach($byte in $inBytes){
$bitstring += [convert]::ToString($byte, 2).PadLeft(8, '0')
}
# Partition the byte string into 7-bit chunks
[byte[]]$key = $bitString -split '(?<=\G.{7}(?<!$))' |ForEach-Object {
# Insert 0 as the least significant bit in each chunk
# Convert resulting string back to [byte]
[convert]::ToByte("${_}0", 2)
}
try{
# Create the first encryptor from our new key, and an empty IV
[byte[]]$iv = ,0 * 8
$enc = $hasher.GetEncryptor($key, $iv)
# Calculate half of the hash
$block1 = $enc.TransformFinalBlock($plaintext, 0, 8)
}
finally{
# Dispose of the encryptor
$enc.Dispose()
}
Then repeat for $str2 and concatenate the resulting blocks for the full LM hash
anyone having issues, based on #mathias R. Jessen
's answer above, here is a fuction that computes half the LM-Hash takes in 7 character string and outputs the hash as Hex.
Function LM-hash {
Param(
[Parameter(mandatory=$true,ValueFromPipeline=$true,position=0)]
[ValidateLength(7,7)]
[String]$Invalue
)
$plaintext = "KGS!##$%"
$OEM = [System.Text.Encoding]::GetEncoding($Host.CurrentCulture.TextInfo.OEMCodePage)
$inBytes = $OEM.GetBytes($invalue)
$bitString = ''
foreach($byte in $inBytes){
$bitstring += [convert]::ToString($byte, 2).PadLeft(8, '0')
}
[byte[]]$key = $bitString -split '(?<=\G.{7}(?<!$))' |ForEach-Object { [convert]::ToByte("${_}0", 2)}
$iv = new-object "System.Byte[]" 8
$DESCSP = New-Object -TypeName System.Security.Cryptography.DESCryptoServiceProvider -Property #{key=$key; IV = $IV; mode = [System.Security.Cryptography.CipherMode]::ECB; Padding=[System.Security.Cryptography.PaddingMode]::None}
$enc = $DESCSP.CreateEncryptor()
$block1 = $enc.TransformFinalBlock($OEM.GetBytes($plaintext), 0, 8)
return [System.BitConverter]::ToString($block1).replace("-","")
$enc.Dispose()
}
this gives the correct result for half the hash, so feeding each half in seperatley and concatenating the strings gives you a full LM hash

Redis Sorted Set: Bulk ZSCORE

How to get a list of members based on their ID from a sorted set instead of just one member?
I would like to build a subset with a set of IDs from the actual sorted set.
I am using a Ruby client for Redis and do not want to iterate one by one. Because there could more than 3000 members that I want to lookup.
Here is the issue tracker to a new command ZMSCORE to do bulk ZSCORE.
There is no variadic form for ZSCORE, yet - see the discussion at: https://github.com/antirez/redis/issues/2344
That said, and for the time being, what you could do is use a Lua script for that. For example:
local scores = {}
while #ARGV > 0 do
scores[#scores+1] = redis.call('ZSCORE', KEYS[1], table.remove(ARGV, 1))
end
return scores
Running this from the command line would look like:
$ redis-cli ZADD foo 1 a 2 b 3 c 4 d
(integer) 4
$ redis-cli --eval mzscore.lua foo , b d
1) "2"
2) "4"
EDIT: In Ruby, it would probably be something like the following, although you'd be better off using SCRIPT LOAD and EVALSHA and loading the script from an external file (instead of hardcoding it in the app):
require 'redis'
script = <<LUA
local scores = {}
while #ARGV > 0 do
scores[#scores+1] = redis.call('ZSCORE', KEYS[1], table.remove(ARGV, 1))
end
return scores
LUA
redis = ::Redis.new()
reply = redis.eval(script, ["foo"], ["b", "d"])
Lua script to get scores with member IDs:
local scores = {}
while #ARGV > 0 do
local member_id = table.remove(ARGV, 1)
local member_score = {}
member_score[1] = member_id
member_score[2] = redis.call('ZSCORE', KEYS[1], member_id)
scores[#scores + 1] = member_score
end
return scores

PID control - value of process parameter based on PID result

I'm trying to implement a PID controller following http://en.wikipedia.org/wiki/PID_controller
The mechanism I try to control works as follows:
1. I have an input variable which I can control. Typical values would be 0.5...10.
2. I have an output value which I measure daily. My goal for the output is roughly at the same range.
The two variables have strong correlation - when the process parameter goes up, the output generally goes up, but there's quite a bit of noise.
I'm following the implementation here:
http://code.activestate.com/recipes/577231-discrete-pid-controller/
Now the PID seems like it is correlated with the error term, not the measured level of output. So my guess is that I am not supposed to use it as-is for the process variable, but rather as some correction to the current value? How is that supposed to work exactly?
For example, if we take Kp=1, Ki=Kd=0, The process (input) variable is 4, the current output level is 3 and my target is a value of 2, I get the following:
error = 2-3 = -1
PID = -1
Then I should set the process variable to -1? or 4-1=3?
You need to think in terms of the PID controller correcting a manipulated variable (MV) for errors, and that you need to use an I term to get to an on-target steady-state result. The I term is how the PID retains and applies memory of the prior behavior of the system.
If you are thinking in terms of the output of the controller being changes in the MV, it is more of a 'velocity form' PID, and the memory of prior errors and behavior is integrated and accumulated in the prior MV setting.
From your example, it seems like a manipulated value of -1 is not feasible and that you would like the controller to suggest a value like 3 to get a process output (PV) of 2. For a PID controller to make use of "The process (input) variable is 4,..." (MV in my terms) Ki must be non-zero, and if the system was at steady-state, whatever was accumulated in the integral (sum_e=sum(e)) would precisely equal 4/Ki, so:
Kp= Ki = 1 ; Kd =0
error = SV - PV = 2 - 3 = -1
sum_e = sum_e + error = 4/Ki -1
MV = PID = -1(Kp) + (4/Ki -1)Ki = -1Kp + 4 - 1*Ki = -1 +4 -1 = 2
If you used a slower Ki than 1, it would smooth out the noise more and not adjust the MV so quickly:
Ki = 0.1 ;
MV = PID = -1(Kp) + (4/Ki -1)Ki = -1Kp + 4 - 1*Ki = -1 +4 -0.1 = 2.9
At steady state at target (PV = SV), sum_e * Ki should produce the steady-state MV:
PV = SV
error = SV - PV = 0
Kp * error = 0
MV = 3 = PID = 0 * Kp + Ki * sum_e
A nice way to understand the PID controller is to put units on everything and think of Kp, Ki, Kd as conversions of the process error, accumulated error*timeUnit, and rate-of-change of error/timeUnit into terms of the manipulated variable, and that the controlled system converts the controller's manipulated variable into units of output.

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