snmptrapd: add larger buffer size than the linux default ones and mak…

…e it customizable via env var

Dockerfile

@@ -13,6 +13,7 @@ RUN apt-get update && \
     snmptrapd=5.9.1+* \
     snmp=5.9.1+* \
     snmp-mibs-downloader=1.5 \
+    pv \
     tzdata ca-certificates
 RUN mkdir /etc/trap2json /etc/trap2json/mibs /var/run/snmptrapd /var/log/trap2json
 COPY --from=buildStage /trap2json /usr/local/bin/trap2json
@@ -23,4 +24,5 @@ RUN chmod +x entrypoint.sh
 EXPOSE 10162/udp
 # prometheus
 EXPOSE 9285
+ENV T2J_BUFFERSIZE=32M
 ENTRYPOINT ["/entrypoint.sh"]

README.md

@@ -47,11 +47,16 @@ Or if you want to pass extra arguments to snmptrapd
 ```shell
 docker run -v ./config.yml:/etc/trap2json/config.yml -p 162:10162/udp bangunindo/trap2json:latest -Lf /var/log/trap2json/snmptrapd.log -Dusm
 ```
+The buffer size for snmptrapd can be customized by setting `T2J_BUFFERSIZE` environment variable.
+By default, it's set to 32M to accommodate trap2json startup time.
+```shell
+docker run -e T2J_BUFFERSIZE=128M -v ./config.yml:/etc/trap2json/config.yml -p 162:10162/udp bangunindo/trap2json:latest
+```
 
 ## Zabbix Forwarder
 For zabbix forwarder to work, you need to create an item with Zabbix Trapper type and text/log data type. If you need
 to map the agent address to host's interface, consider using the `advanced` section of `zabbix_trapper` config in [config.yml](config.yml).
 
 Zabbix limits its text/log type to 65536 characters/bytes (depending on backend). In most cases you probably will
 not meet this limitation. But when it does, you might want to create a smaller json schema with only the data
-you want.
+you want.

entrypoint.sh

@@ -2,4 +2,4 @@
 set -e
 trap2json -generate /etc/trap2json/snmptrapd.conf
 shopt -s lastpipe
-snmptrapd -M +/etc/trap2json/mibs -m ALL -Lo -OnUx -f -C -c /etc/trap2json/snmptrapd.conf $@ | exec trap2json
+snmptrapd -M +/etc/trap2json/mibs -m ALL -Lo -OnUx -f -C -c /etc/trap2json/snmptrapd.conf $@ | pv -q -B "${T2J_BUFFERSIZE:-32M}" | exec trap2json