SNMP简单网络管理协议
简单网络管理协议(SNMP-Simple Network Management Protocol)是一个与网络设备交互的简单方法。该规范是由IETF在1990年五月发布的RFC 1157中定义的,是各种管理应用程序用来控制设备的方法
一个网络设备以守护进程的方式运行SNMP代理,该守护进程能够响应来自网络的各种请求信息。该SNMP代理提供大量的对象标识符(OID-Object Identifiers)。一个OID是一个唯一的键值对。该代理存放这些值并让它们可用。一个SNMP管理器(客户)可以向代理查询键值对中的特定信息。SNMP中有一个基本的认证框架,能够让管理员发送公共名来对OID读取或写入的认证。绝大多数的设备使用不安全的公共名 "public" 。 SNMP协议通过UDP端口161和162进行通信的。
SNMP的常用版本有三个:SNMPv1、SNMPv2、SNMPv3。
SNMP简介:https://blog.csdn.net/u011857683/article/details/79915260
几款关于SNMP的调试工具:
ManageEngine MibBrowser(适用与有现成的.mib库文件)
Paessler SNMP Tester(测试OID)
FreeSnmp(使用Walk探测OID)
Snmputil工具
1 OID信息
https://blog.51cto.com/lanfenggo/1840427
OID(对象标识符),是SNMP代理提供的具有唯一标识的键值。MIB(管理信息基)提供数字化OID到可读文本的映射。
根据oid获取到的内存信息可能是英文,也可能是ascii码,还可能是其他编码,这时候不能根据单纯通过“1.3.6.1.2.1.25.2.3.1.3”取到的内存名称来判断,可参考以下信息:
“1.3.6.1.2.1.25.2.1.3”<==>虚拟内存
"1.3.6.1.2.1.25.2.1.2"<==>物理内存
2 snmp 安装配置
3 Snmputil工具
SugarNMSTool 网络管理工具(SNMP工具、网络管理、网络分析等):https://www.jb51.net/softs/439487.html
Snmputil工具:https://www.jb51.net/softs/563509.html
4 java代码调用
引入jar包
<!--snmp--> <dependency> <groupId>org.snmp4j</groupId> <artifactId>snmp4j</artifactId> <version>2.5.0</version> </dependency>
示例java代码
import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.snmp4j.*; import org.snmp4j.event.ResponseEvent; import org.snmp4j.mp.MessageProcessingModel; import org.snmp4j.mp.SnmpConstants; import org.snmp4j.smi.*; import org.snmp4j.transport.DefaultUdpTransportMapping; import org.snmp4j.util.PDUFactory; import org.snmp4j.util.TableEvent; import org.snmp4j.util.TableUtils; import java.io.IOException; import java.util.List; public class Snmp4Uitl { private static final Logger log = LoggerFactory.getLogger(Snmp4Uitl.class); private static final String IP ="10.243.141.114"; public static void main(String[] args) throws IOException { List<TableEvent> aPublic = getTable(IP, new String[]{"1.3.6.1.2.1.25.2.3.1.2"}, "public"); long sum = 0; for (TableEvent event : aPublic) { System.out.println(event.getColumns()[0].getVariable().toString()); // sum +=event.getColumns()[0].getVariable().toLong(); } /* PDU pdu = send(IP ,"1.3.6.1.2.1.25.2.3.1.5", "public" ); System.out.println(pdu.get(0).getVariable().toString());*/ // log.info(sum /1024L +""); } public static PDU send(String ip, String oid, String community) throws IOException { TransportMapping<UdpAddress> transportMapping = new DefaultUdpTransportMapping(); Snmp snmp = new Snmp(transportMapping); try { snmp.listen(); ResponseEvent response = null; PDU pdu = new PDU(); pdu.add(new VariableBinding(new OID(oid))); pdu.setType(PDU.GET); String address = ip + "/" + 161; Address targetAddress = new UdpAddress(address); CommunityTarget target = new CommunityTarget(); target.setCommunity(new OctetString(community)); // 改字符串是我们在上面配置的 target.setAddress(targetAddress); target.setRetries(2); target.setTimeout(3000); target.setVersion(SnmpConstants.version2c); response = snmp.get(pdu, target); PDU result = response.getResponse(); if (result == null) { throw new RuntimeException("连接失败" + address + " community:" + community); } return result; } catch (Exception ex) { throw ex; } finally { snmp.close(); } } public static List<TableEvent> getTable(String ip, String[] oids, String community) throws IOException { TransportMapping transport = null; Snmp snmp = null; CommunityTarget target; try { transport = new DefaultUdpTransportMapping(); snmp = new Snmp(transport);//创建snmp snmp.listen();//监听消息 target = new CommunityTarget(); target.setCommunity(new OctetString(community)); target.setRetries(2); target.setAddress(GenericAddress.parse("udp:" + ip + "/161")); target.setTimeout(8000); target.setVersion(SnmpConstants.version2c); TableUtils tableUtils = new TableUtils(snmp, new PDUFactory() { @Override public PDU createPDU(Target arg0) { PDU request = new PDU(); request.setType(PDU.GET); return request; } @Override public PDU createPDU(MessageProcessingModel messageProcessingModel) { PDU request = new PDU(); request.setType(PDU.GET); return request; } }); OID[] columns = new OID[oids.length]; for (int i = 0; i < oids.length; i++) columns[i] = new OID(oids[i]); List<TableEvent> list = tableUtils.getTable(target, columns, null, null); return list; } catch (Exception e) { throw e; } finally { try { if (transport != null) transport.close(); if (snmp != null) snmp.close(); } catch (IOException e) { log.error("Snmp4Uitl[]getTable[]error", e); } } } }