SNMP/No Bufferspace

[Eugene Grosbein]

04.06.2019 0:49, Larry Rosenman wrote:

> On 06/03/2019 12:23 pm, Eugene Grosbein wrote:
>> 03.06.2019 22:56, Larry Rosenman wrote:
>>
>>> I have a mrtg job that runs every 5 minutes on a FreeBSD-CURRENT box and gets this randomly:
>>>
>>> SNMP Error:
>>> send_query: No buffer space available
>>
>> [skip]
>>
>>> How can I debug this?
>>
>> Your outgoing network interface stalls for some reason.
>> Where is this traffic directed to? Some kind of VPN tunnel? Physical
>> NIC that looses link?
>> Some Wifi or mobile network?
>>
> physical NIC on the same physical network (all Ubiquiti gear).
> 
> 
> ⌂66% [ler at borg.lerctr.org:~] $ ifconfig
> lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
>     options=680003<RXCSUM,TXCSUM,LINKSTATE,RXCSUM_IPV6,TXCSUM_IPV6>
>     inet6 ::1 prefixlen 128
>     inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
>     inet 127.0.0.1 netmask 0xff000000
>     groups: lo
>     nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
> bce0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
>     options=c01bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,VLAN_HWTSO,LINKSTATE>
>     ether a4:ba:db:29:66:95
>     media: Ethernet autoselect (1000baseT <full-duplex>)
>     status: active
>     nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
> bce1: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
>     options=c01bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,VLAN_HWTSO,LINKSTATE>
>     ether a4:ba:db:29:66:97
>     media: Ethernet autoselect
>     nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
> bce2: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
>     options=c01bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,VLAN_HWTSO,LINKSTATE>
>     ether a4:ba:db:29:66:99
>     media: Ethernet autoselect
>     nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
> bce3: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
>     options=c01bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,VLAN_HWTSO,LINKSTATE>
>     ether a4:ba:db:29:66:9b
>     media: Ethernet autoselect
>     nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
> bridge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
>     ether 02:d7:b8:51:f2:00
>     inet6 fe80::d7:b8ff:fe51:f200%bridge0 prefixlen 64 scopeid 0x6
>     inet6 2600:1700:210:b180:d7:b8ff:fe51:f200 prefixlen 64 autoconf
>     inet 192.168.200.4 netmask 0xfffffc00 broadcast 192.168.203.255
>     id 00:00:00:00:00:00 priority 32768 hellotime 2 fwddelay 15
>     maxage 20 holdcnt 6 proto rstp maxaddr 2000 timeout 1200
>     root id 00:00:00:00:00:00 priority 32768 ifcost 0 port 0
>     member: bce0 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
>             ifmaxaddr 0 port 2 priority 128 path cost 55
>     groups: bridge
>     nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>
> ⌂68% [ler at borg.lerctr.org:~] $
> 
> bridge0 via bce0 to the "main-switch" . and all the
> AP's,switches, etc.

You should search system logs for possible link problems
and check counters shown by "netstat -idnh" (errs/drop/coll).

Also check counters by "netstat -m" for mbufs/mbuf clusters.