一. 交换机开启SNMP协议

snmp-agent sys-info version v2 #v2为snmp协议版本
snmp-agent community read ci test1234 #团体名
snmp-agent trap enable
snmp-agent target-host trap address udp-domain 192.168.1.9 params securityname Public123456 #允许向snmp服务器发送trap报文

二. 部署snmp_exporter

github官方地址: https://github.com/prometheus/snmp_exporter

1、下载snmp_exporter

wget https://github.com/prometheus/snmp_exporter/releases/download/v0.19.0/snmp_exporter-0.19.0.linux-amd64.tar.gz
tar xf snmp_exporter-0.19.0.linux-amd64.tar.gz -C /opt/

2、编译安装generator,生成snmp_exporter配置文件snmp.yml

generator:使用netsnmp解析mibs,通过它为snmp_exporter生成配置文件信息

2.1 安装Go环境

golang官方下载地址:https://golang.org/dl/

wget https://dl.google.com/go/go1.11.5.linux-amd64.tar.gz
tar xf go1.11.5.linux-amd64.tar.gz -C /usr/local/
vim /etc/profile
export GOROOT=/usr/local/go
export PATH=$PATH:$GOROOT/bin
EOF
source /etc/profile
go version #显示版本号即安装成功

2.2 编译安装generator

yum install gcc gcc-g++ make net-snmp net-snmp-utils net-snmp-libs net-snmp-devel -y
go get github.com/prometheus/snmp_exporter/generator
cd ${GOPATH-$HOME/go}/src/github.com/prometheus/snmp_exporter/generator
go build
make mibs #如果已下载相关设备厂家提供的mib文件则无需再次生成mib库,跳过此步

2.3 获取需要监控的硬件设备mib库

去相关交换机厂商官方地址下载相关mib文件

APC

Servertech

Palo Alto PanOS 7.0 enterprise MIBs

Arista Networks

Arista Networks

Arista Networks

Synology

MikroTik

UCD-SNMP-MIB(Net-SNMP)

Ubiquiti Networks

Ubiquiti Networks

Ubiquiti Networks

Cisco

将获取的mib文件上传至${GOPATH-$HOME/go}/src/github.com/prometheus/snmp_exporter/generator

2.4 编写generator配置文件

generator.yml提供模块列表。最简单的模块只是一个name和一组walk的oid

github官方地址:

modules:
  module_name:  # The module name. You can have as many modules as you want.
    walk:       # List of OIDs to walk. Can also be SNMP object names or specific instances.
      - 1.3.6.1.2.1.2              # Same as "interfaces"
      - sysUpTime                  # Same as "1.3.6.1.2.1.1.3"
      - 1.3.6.1.2.1.31.1.1.1.6.40  # Instance of "ifHCInOctets" with index "40"

    version: 2  # SNMP version to use. Defaults to 2.
                # 1 will use GETNEXT, 2 and 3 use GETBULK.
    max_repetitions: 25  # How many objects to request with GET/GETBULK, defaults to 25.
                         # May need to be reduced for buggy devices.
    retries: 3   # How many times to retry a failed request, defaults to 3.
    timeout: 5s  # Timeout for each individual SNMP request, defaults to 5s.

    auth:
      # Community string is used with SNMP v1 and v2. Defaults to "public".
      community: public

      # v3 has different and more complex settings.
      # Which are required depends on the security_level.
      # The equivalent options on NetSNMP commands like snmpbulkwalk
      # and snmpget are also listed. See snmpcmd(1).
      username: user  # Required, no default. -u option to NetSNMP.
      security_level: noAuthNoPriv  # Defaults to noAuthNoPriv. -l option to NetSNMP.
                                    # Can be noAuthNoPriv, authNoPriv or authPriv.
      password: pass  # Has no default. Also known as authKey, -A option to NetSNMP.
                      # Required if security_level is authNoPriv or authPriv.
      auth_protocol: MD5  # MD5, SHA, SHA224, SHA256, SHA384, or SHA512. Defaults to MD5. -a option to NetSNMP.
                          # Used if security_level is authNoPriv or authPriv.
      priv_protocol: DES  # DES, AES, AES192, or AES256. Defaults to DES. -x option to NetSNMP.
                          # Used if security_level is authPriv.
      priv_password: otherPass # Has no default. Also known as privKey, -X option to NetSNMP.
                               # Required if security_level is authPriv.
      context_name: context # Has no default. -n option to NetSNMP.
                            # Required if context is configured on the device.

    lookups:  # Optional list of lookups to perform.
              # The default for `keep_source_indexes` is false. Indexes must be unique for this option to be used.

      # If the index of a table is bsnDot11EssIndex, usually that'd be the label
      # on the resulting metrics from that table. Instead, use the index to
      # lookup the bsnDot11EssSsid table entry and create a bsnDot11EssSsid label
      # with that value.
      - source_indexes: [bsnDot11EssIndex]
        lookup: bsnDot11EssSsid
        drop_source_indexes: false  # If true, delete source index labels for this lookup.
                                    # This avoids label clutter when the new index is unique.

     overrides: # Allows for per-module overrides of bits of MIBs
       metricName:
         ignore: true # Drops the metric from the output.
         regex_extracts:
           Temp: # A new metric will be created appending this to the metricName to become metricNameTemp.
             - regex: '(.*)' # Regex to extract a value from the returned SNMP walks's value.
               value: '$1' # The result will be parsed as a float64, defaults to $1.
           Status:
             - regex: '.*Example'
               value: '1' # The first entry whose regex matches and whose value parses wins.
             - regex: '.*'
               value: '0'
         type: DisplayString # Override the metric type, possible types are:
                             #   gauge:   An integer with type gauge.
                             #   counter: An integer with type counter.
                             #   OctetString: A bit string, rendered as 0xff34.
                             #   DateAndTime: An RFC 2579 DateAndTime byte sequence. If the device has no time zone data, UTC is used.
                             #   DisplayString: An ASCII or UTF-8 string.
                             #   PhysAddress48: A 48 bit MAC address, rendered as 00:01:02:03:04:ff.
                             #   Float: A 32 bit floating-point value with type gauge.
                             #   Double: A 64 bit floating-point value with type gauge.
                             #   InetAddressIPv4: An IPv4 address, rendered as 1.2.3.4.
                             #   InetAddressIPv6: An IPv6 address, rendered as 0102:0304:0506:0708:090A:0B0C:0D0E:0F10.
                             #   InetAddress: An InetAddress per RFC 4001. Must be preceded by an InetAddressType.
                             #   InetAddressMissingSize: An InetAddress that violates section 4.1 of RFC 4001 by
                             #       not having the size in the index. Must be preceded by an InetAddressType.
                             #   EnumAsInfo: An enum for which a single timeseries is created. Good for constant values.
                             #   EnumAsStateSet: An enum with a time series per state. Good for variable low-cardinality enums.
                             #   Bits: An RFC 2578 BITS construct, which produces a StateSet with a time series per bit.

这里generator.yml需要注意两点

2.4.1 walk下面写的是你需要查询的信息对应的oid,这个像华为交换机都是可以在原厂文档上查的到的;要监控交换机的端口流量、状态,CPU使用率,内存状态,温度等,关键是找出与之相对应的oid
oid信息可参考如下地址:http://oid-info.com/

获取到的监控信息相关的oid可通过snmpwalk过滤查询

snmpwalk命令格式如下:

snmpwalk -v "snmp版本" -c "coummunity" IP oid(可选)
#通过snmpwalk查询过滤出有值的数据,获取子节点值
snmpwalk -v 2c -c test1234 192.168.1.100 1.3.6.1.4.1.2011.5.25.31.1.1.1.1.11|grep -v 0$

2.4.2 还有一点就是community这个要写自己设置的团体名,如果不知道可以自己手动设置一个,我这里设置的是test1234

其他的地方基本不需要修改,模块名也可以改,后面使用snmp查的时候、写prometheus配置文件的时候对应也写自己刚刚修改的mib名称就好。

numAsInfo和EnumAsStateSet

SNMP包含整数索引枚举(枚举)的概念。在Prometheus中有两种表示这些字符串的方法。它们可以是“信息”指标,也可以是“状态集”。SNMP没有指定应使用的内容,这取决于数据的使用情况。一些用户可能更喜欢原始整数值,而不是字符串。

为了将枚举整数设置为字符串映射,必须使用两个替代之一。

EnumAsInfo应该用于提供类似库存数据的属性。例如设备类型,颜色名称等。此值必须恒定。

EnumAsStateSet应该用于表示状态或您可能需要警惕的事物。例如,链接状态是打开还是关闭,处于错误状态,面板是打开还是关闭等。请注意不要将其用于高基数值,因为它将为每个可能的值生成1个时间序列。

2.5 运行generator生成snmp.yml

export MIBDIRS=mibs #指定mib库路径
./generator generate
cp snmp.yml /usr/local/snmp_exporter/ #将生成的snmp配置移到snmp_exporter目录下

3、运行snmp_exporter

./snmp_exporter --config.file=/usr/local/snmp_exporter/snmp.yml

比较大的counter类型数据的值如何处理

为了为Counter64较大的值提供准确的计数器,snmp_exporter将每2 ^ 53自动包装该值,以避免64位浮点舍入,

要禁用此功能,可使用命令行参数-no-snmp.wrap-large-counters

4、测试

访问192.168.1.9:9116

traget:192.168.1.222 #snmp设备

module:huawei_mib #模块名,与generator.yml中设置的模块名保持一致

点击提交,可获取snmp数据

三、配置prometheus

1、修改prometheus.yml

在scrape_configs数据抓取配置中加入以下配置信息

scrape_configs:
  - job_name: 'snmp'
    static_configs:
      - targets:
        - 192.168.1.222  # SNMP device.
    metrics_path: /snmp
    params:
      module: [if_mib]
    relabel_configs:
      - source_labels: [__address__]
        target_label: __param_target
      - source_labels: [__param_target]
        target_label: instance
      - target_label: __address__
        replacement: 192.168.1.9:9116  # The SNMP exporter's real hostname:port.

2、重启prometheus

curl -X POST http://localhost:9090/-/reload #如果prometheus启动参数有--web.enable-lifecycle,可通过此命令平滑重启

四、grafana数据可视化

根据snmp_exporter查询到的HELP后查到的参数信息,进行图形化显示。大家可以根据自己的需要去查相应的参数信息,如果想查更多的信息,基本上的流程就是:

1、将需要查询的交换机信息oid加入到generator.yml文件

2、重新编译generator.yml文件生成snmp.yml文件

3、替换原来的snmp.yml文件

4、重启snmp_exporter