PySNMP 是一个纯粹用Python实现的SNMP,用PySNMP的最抽象的API为One-line Applications,其中有两类API：同步的和非同步的,都在模块pysnmp.entity.rfc3413.oneliner.cmdgen 中实现,如下是Get方式与Walk方式的基本实现.
首先需要在系统中安装SNMP客户端,对于Linux平台来说只需要执行如下配置过程即可.
[root@localhost ~]# yum install -y net-snmp [root@localhost ~]# cat /etc/snmp/snmpd.conf |grep -vE "^#|^$" com2sec notConfigUser default public group notConfigGroup v1 notConfigUser group notConfigGroup v2c notConfigUser view systemview included .1 view systemview included .1 access notConfigGroup "" any noauth exact systemview none none [root@localhost ~]# systemctl restart snmpd [root@localhost ~]# systemctl enable snmpd 如果是Windows系统则需要在客户机服务列表，开启SNMP支持，并设置好一个团体名称，如下图。
当我们配置好客户端后，服务端就客户获取数据了，我们以一个OID序号为例，我们查询特定序号对应的名称，然后将其记录下来，例如下面这样。
C:Usersadmin> snmpwalk -v 2c -c public 192.168.1.101 .1.3.6.1.2.1.25.2.2 HOST-RESOURCES-MIB::hrMemorySize.0 = INTEGER: 2096632 KBytes 首先我们不使用PySNMP模块直接开线程调用看看,该代码如下所示.
import os,re,time # 通过SNMP收集主机CPU利用率: 通过SNMP协议,收集目标主机的CPU利用率(百分比),并返回JSON字符串. def Get_CPU_Info(addr): try: Head = ["HostName","CoreLoad","CpuUser","CpuSystem","CpuIdle"] CPU = [] ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " .1.3.6.1.2.1.1.5") CPU.append(ret.read().split(":")[3].strip()) ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " .1.3.6.1.2.1.25.3.3.1.2") CPU.append(ret.read().split(":")[3].strip()) for i in [9,10,11]: ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " 1.3.6.1.4.1.2021.11.{}.0".format(i)) ret = ret.read() Info = ret.split(":")[3].strip() CPU.append(Info) return dict(zip(Head,CPU)) except Exception: return 0 # 通过SNMP获取系统CPU负载信息: 分别获取到系统的1,5,15分钟的负载信息,并返回JSON格式. def Get_Load_Info(addr): try: Head = ["HostName","Load1","Load5","Load15"] SysLoad = [] ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " .1.3.6.1.2.1.1.5") SysLoad.append(ret.read().split(":")[3].strip()) ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " .1.3.6.1.4.1.2021.10.1.3") load = list(re.sub(".*STRING: ", "", ret.read()).split("n")) SysLoad.append(load[0]) SysLoad.append(load[1]) SysLoad.append(load[2]) return dict(zip(Head,SysLoad)) except Exception: return 0 # 通过SNMP获取系统内存占用: 内存利用率，获取到之后，将其转化为字典格式保存。 def Get_Mem_Info(addr): try: Head = ["HostName","memTotalSwap","memAvailSwap","memTotalReal","memTotalFree"] SysMem = [] ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " .1.3.6.1.2.1.1.5") SysMem.append(ret.read().split(":")[3].strip()) ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " .1.3.6.1.4.1.2021.4") mem = ret.read().split("n") for i in [2,3,4,6]: SysMem.append(re.sub(".*INTEGER: ","",mem[i]).split(" ")[0]) return dict(zip(Head,SysMem)) except Exception: return 0 # 通过SNMP获取系统磁盘数据: 这个案例并不完整,我只写了一点,后面有个问题一直没有解决. def Get_Disk_Info(addr): try: dic = {} list = [] ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " HOST-RESOURCES-MIB::hrStorageDescr") DiskName = ret.read().split("n") ret =os.popen("snmpwalk -v 2c -c nmap " + addr + " HOST-RESOURCES-MIB::hrStorageUsed") DiskUsed = ret.read().split("n") ret = os.popen("snmpwalk -v 2c -c nmap " + addr + " HOST-RESOURCES-MIB::hrStorageSize") DiskSize = ret.read().split("n") for i in range(1,len(DiskName) - 7): dic["Name"]= DiskName[i + 5].split(":")[3] dic["Used"]= DiskUsed[i + 5].split(":")[3] dic["Size"]= DiskSize[i + 5].split(":")[3] list.append(dic) return list except Exception: return 0 if __name__ == '__main__': for i in range(100): dic = Get_CPU_Info("192.168.1.20") print(dic) time.sleep(1) 我们使用pysnmp模块来做，安装pysnmp很简单，执行命令pip install pysnmp 即可，安装后使用以下代码执行即可获取到目标数据，获取方式分为两种一种为Get另一种为Walk.
from pysnmp.hlapi import * import os,sys class NetSNMP(): def __init__(self,address,region): self.region = region self.address = address # 获取指定数据的方法 def GetNumber(self,oid,sub_oid,sub_id): iterator = getCmd(SnmpEngine(), CommunityData(self.region), UdpTransportTarget((self.address, 161)), ContextData(), ObjectType(ObjectIdentity(oid, sub_oid, sub_id))) errorIndication, errorStatus, errorIndex, varBinds = next(iterator) if errorIndication: return False else: if errorStatus: return False else: for varBind in varBinds: return [x.prettyPrint() for x in varBind] # 使用Walk拉取数据 def WalkNumber(self, oid): res = [] for (errorIndication, errorStatus, errorIndex, varBinds) in nextCmd(SnmpEngine(), CommunityData(self.region),UdpTransportTarget((self.address, 161)),ContextData(), ObjectType(ObjectIdentity(oid)).addMibSource( './site-packages/pysnmp/smi/mibs','pysnmp_mibs'),lexicographicMode=False): if errorIndication: print(errorIndication, file=sys.stderr) break elif errorStatus: print('%s at %s' % (errorStatus.prettyPrint(), errorIndex and varBinds[int(errorIndex) - 1][0] or '?'), file=sys.stderr) break else: for varBind in varBinds: res.append(str(varBind)) return res if __name__ == "__main__": # 初始化 ptr = NetSNMP("192.168.81.130","public") # 使用GET方式获取OID数据 ret = ptr.GetNumber("HOST-RESOURCES-MIB","hrMemorySize",0) print("类型: {} --> 返回结果: {} --> 解析: {}".format(type(ret),ret,ret[1])) # 使用Walk方式获取OID数据 ret = ptr.WalkNumber(".1.3.6.1.2.1.2.2.1.6") for each in ret: mac = each.split("=")[1] if len(mac) > 1: print("网卡接口: {}".format(mac)) 
