Sorry for all the noise, but I finally figured out how to use the tagpass/tagdrop to route the telegraf inputs to two separate InfluxDBs on the same server.
[[outputs.influxdb]]
urls = ["http://tick-alln-001:8086"] # required
## The target database for metrics (telegraf will create it if not exists).
database = "telegraf" # required
[outputs.influxdb.tagdrop]
source = ["prodvcs"]
# Define a database for vcs collectd metrics
[[outputs.influxdb]]
urls = ["http://tick-alln-001:8086"]
database = "vcs"
# Only accept the vcs collecd metrics in this database
[outputs.influxdb.tagpass]
source = ["prodvcs"]
[[inputs.socket_listener]]
# Receive collectd stats from VCS devices
service_address = "udp://0.0.0.0:25826"
data_format = "collectd"
# ## Path of to TypesDB specifications
collectd_typesdb = ["/usr/share/collectd/types.db"]
[inputs.socket_listener.tags]
source = "prodvcs"