Integración de SNMP

En esta sección se describe cómo configurar la integración del protocolo simple de administración de redes (Simple Network Management Protocol, SNMP).

Para obtener más información sobre la configuración de SNMP, consulte la documentación de Net-SNMP. Para configurar la integración de SNMP, siga estos pasos:

1. Edite /etc/snmp/snmpd.conf.
2. Agregue las siguientes líneas al archivo config con la dirección IP de origen de los sistemas que se deben conectar al servicio SNMP. Puede configurar mediante SNMPv2c o SNMPv3.
   • En el siguiente ejemplo, se configura el acceso a todos los contadores desde localhost a través de la cadena de comunidad vc-vcg y desde 10.0.0.0/8 con la cadena de comunidad myentprisecommunity, utilizando la versión SNMPv2c.

     agentAddress udp:161
     # com2sec sec.name source community
     com2sec local localhost vc-vcg
      com2sec myenterprise 10.0.0.0/8 myentprisecommunity# group access.name sec.model sec.name 
     group rogroup v2c local
      group rogroup v2c myenterpriseview all included .1 80 
     # access access.name context sec.model sec.level match read write notif
     access rogroup "" any noauth exact all none none#sysLocation Sitting on the Dock of the Bay
     #sysContact Me <[email protected]>sysServices 72master agentx#
     # Process Monitoring
     ## At least one 'gwd' process
     proc gwd
     # At least one 'mgd' process
     proc mgd#
     # Disk Monitoring
     #
     # 100MBs required on root disk, 5% free on /var, 10% free on all other disks
     disk / 100000
     disk /var 5%
     includeAllDisks 10%#
     # System Load
     #
     # Unacceptable 1-, 5-, and 15-minute load averages
     load 12 10 5
     #  "Pass-through" MIB extension command
     pass_persist  .1.3.6.1.4.1.45346 /opt/vc/bin/snmpagent.py veloGateway

     Nota: En el ejemplo anterior, el proceso gwd comprende todo el plano de control y datos de la puerta de enlace. El daemon del plano de administración (mgd) es responsable de la comunicación con Orchestrator. Este proceso se mantiene aislado de gwd para que, en el caso de un error total del proceso de gwd, se pueda acceder a Orchestrator para realizar cambios de configuración o actualizaciones de software que se requieran para resolver el error.
   • En el siguiente ejemplo se muestra la configuración usando la versión SNMPv3.

     vcadmin:~$ cat /etc/snmp/snmpd.conf 
     ###############################################################################
     #
     # EXAMPLE.conf:
     #  An example configuration file for configuring the Net-SNMP agent ('snmpd')
     #  See the 'snmpd.conf(5)' man page for details
     #
     #  Some entries are deliberately commented out, and will need to be explicitly activated
     #
     ###############################################################################
     #
     #  AGENT BEHAVIOUR
     #
     
     #  Listen for connections from the local system only
     # agentAddress  udp:127.0.0.1:161
     #  Listen for connections on all interfaces (both IPv4 *and* IPv6)
     agentAddress udp:161
     
     ###############################################################################
     #
     #  SNMPv3 AUTHENTICATION
     #
     #  Note that these particular settings don't actually belong here.
     #  They should be copied to the file /var/lib/snmp/snmpd.conf
     #     and the passwords changed, before being uncommented in that file *only*.
     #  Then restart the agent
     #  createUser authOnlyUser  MD5 "remember to change this password"
     #  createUser authPrivUser  SHA "remember to change this one too"  DES
     #  createUser internalUser  MD5 "this is only ever used internally, but still change the password"
     
     #  If you also change the usernames (which might be sensible),
     #  then remember to update the other occurances in this example config file to match.
     
     
     
     ###############################################################################
     #
     #  ACCESS CONTROL
     #
     
     #  system + hrSystem groups only
        view   systemonly  included   .1.3.6.1.4.1.45346
     
     #  Full access from the local host
     #  rocommunity public  localhost
     #  Default access to basic system info
        rocommunity public  default    -V systemonly
     
     #  Full access from an example network
     #  Adjust this network address to match your local settings, change the community string,
     #  and check the 'agentAddress' setting above
        rocommunity secret  10.0.0.0/16
     
     #  Full read-only access for SNMPv3
        rouser   authOnlyUser
     #  Full write access for encrypted requests 
     #  Remember to activate the 'createUser' lines above
        rwuser   authPrivUser   priv
     
     #  It's no longer typically necessary to use the full 'com2sec/group/access' configuration
     #  r[ow]user and r[ow]community, together with suitable views, should cover most requirements
     
     ###############################################################################
     #
     #  SYSTEM INFORMATION
     #
     #  Note that setting these values here, results in the corresponding MIB objects being 'read-only'
     #  See snmpd.conf(5) for more details
     sysLocation    Bay
     sysContact     [email protected]
     # Application + End-to-End layers
     sysServices    72
     
     
     #
     #  Process Monitoring
     #
     # At least one  'mountd' process
     proc  mountd
     
     # No more than 4 'ntalkd' processes - 0 is OK
     proc  ntalkd    4
     
     # At least one 'sendmail' process, but no more than 10
     proc  sendmail 10 1
     
     #  Walk the UCD-SNMP-MIB::prTable to see the resulting output
     #  Note that this table will be empty if there are no "proc" entries in the snmpd.conf file
     
     #
     #  Disk Monitoring
     #
     # 10MBs required on root disk, 5% free on /var, 10% free on all other disks
     disk       /     10000
     disk       /var  5%
     includeAllDisks  10%
     
     #  Walk the UCD-SNMP-MIB::dskTable to see the resulting output
     #  Note that this table will be empty if there are no "disk" entries in the snmpd.conf file
     
     
     #
     #  System Load
     #
     # Unacceptable 1-, 5-, and 15-minute load averages
     load   12 10 5
     
     #  Walk the UCD-SNMP-MIB::laTable to see the resulting output
     #  Note that this table *will* be populated, even without a "load" entry in the snmpd.conf file
     
     ###############################################################################
     #
     #  ACTIVE MONITORING
     #
     #   send SNMPv1  traps
       trapsink     localhost public
     #   send SNMPv2c traps
       trap2sink    localhost public
     #   send SNMPv2c INFORMs
       informsink   localhost public
     
     #  Note that you typically only want *one* of these three lines
     #  Uncommenting two (or all three) will result in multiple copies of each notification.
     
     #
     #  Event MIB - automatically generate alerts
     #
     # Remember to activate the 'createUser' lines above
     iquerySecName   internalUser
     rouser          internalUser
     # generate traps on UCD error conditions
     defaultMonitors          yes
     # generate traps on linkUp/Down
     linkUpDownNotifications  yes
     
     ###############################################################################
     #
     #  EXTENDING THE AGENT
     
     #
     #  Arbitrary extension commands
     #
      extend    test1   /bin/echo  Hello, world!
      extend-sh test2   echo Hello, world! ; echo Hi there ; exit 35
     #extend-sh test3   /bin/sh /tmp/shtest
     
     #  Note that this last entry requires the script '/tmp/shtest' to be created first,
     #    containing the same three shell commands, before the line is uncommented
     
     #  Walk the NET-SNMP-EXTEND-MIB tables (nsExtendConfigTable, nsExtendOutput1Table
     #     and nsExtendOutput2Table) to see the resulting output
     
     #  Note that the "extend" directive supercedes the previous "exec" and "sh" directives
     #  However, walking the UCD-SNMP-MIB::extTable should still returns the same output,
     #     as well as the fuller results in the above tables.
     
     
     #
     #  "Pass-through" MIB extension command
     #
     #pass .1.3.6.1.4.1.8072.2.255  /bin/sh       PREFIX/local/passtest
     #pass .1.3.6.1.4.1.8072.2.255  /usr/bin/perl PREFIX/local/passtest.pl
     
     rocommunity velocloud localhost
     #pass  .1.3.6.1.4.1.45346 /opt/vc/bin/snmpagent.py veloGateway
     pass_persist  .1.3.6.1.4.1.45346 /opt/vc/bin/snmpagent.py veloGateway
     
     # Note that this requires one of the two 'passtest' scripts to be installed first,
     #    before the appropriate line is uncommented.
     # These scripts can be found in the 'local' directory of the source distribution,
     #     and are not installed automatically.
     
     #  Walk the NET-SNMP-PASS-MIB::netSnmpPassExamples subtree to see the resulting output
     
     #
     #  AgentX Sub-agents
     #
     #  Run as an AgentX master agent
      master          agentx
     #  Listen for network connections (from localhost)
     #    rather than the default named socket /var/agentx/master

3. Edite /etc/iptables/rules.v4. Agregue las siguientes líneas a la configuración con la IP de origen de los sistemas que se deben conectar al servicio SNMP:

   # WARNING: only add targeted rules for addresses and ports
   # do not add blanket drop or accept rules since Gateway will append its own rules
   # and that may prevent it from functioning properly
   *filter
   :INPUT ACCEPT [0:0]
   -A INPUT -p udp -m udp --source 127.0.0.1 --dport 161 -m comment --comment "allow SNMP port" -j ACCEPT
   -A INPUT -p udp -m udp --source 10.0.0.0/8 --dport 161 -m comment --comment "allow SNMP port" -j ACCEPT
   :FORWARD ACCEPT [0:0]
   :OUTPUT ACCEPT [0:0]
   COMMIT

4. Reinicie los servicios snmp e iptables siguientes:

   service snmpd restart
   service iptables-persistent restart
   service vc_process_monitor restart