kafka: client has run out of available brokers to talk to (Is your cluster reachable?) #183

vflow can't connect to kafka. the error is
[vflow] 2023/01/11 09:25:26 Welcome to vFlow v.0.4.1 Apache License 2.0
[vflow] 2023/01/11 09:25:26 Copyright (C) 2017 Verizon. github.com/VerizonDigital/vflow
[vflow] 2023/01/11 09:25:26 starting stats web server ...
[vflow] 2023/01/11 09:25:26 ipfix has been disabled
[vflow] 2023/01/11 09:25:26 netflowv9 has been disabled
[vflow] 2023/01/11 09:25:26 sFlow is running (UDP: listening on [::]:6343 workers#: 300)
[vflow] 2023/01/11 09:25:26 rcvd sflow data from: 10.1.1.93:6343, size: 1100 bytes
[vflow] 2023/01/11 09:25:26 rcvd sflow data from: 10.1.1.93:6343, size: 904 bytes
[vflow] 2023/01/11 09:25:27 rcvd sflow data from: 10.1.1.93:6343, size: 628 bytes
[vflow] 2023/01/11 09:25:27 rcvd sflow data from: 10.1.1.93:6343, size: 564 bytes
[vflow] 2023/01/11 09:25:27 rcvd sflow data from: 10.1.1.93:6343, size: 328 bytes
[vflow] 2023/01/11 09:25:27 rcvd sflow data from: 10.1.1.93:6343, size: 260 bytes
[vflow] 2023/01/11 09:25:28 rcvd sflow data from: 10.1.1.93:6343, size: 804 bytes
[vflow] 2023/01/11 09:25:28 rcvd sflow data from: 10.1.1.93:6343, size: 492 bytes
[vflow] 2023/01/11 09:25:28 rcvd sflow data from: 10.1.1.93:6343, size: 328 bytes
[vflow] 2023/01/11 09:25:29 rcvd sflow data from: 10.1.1.93:6343, size: 628 bytes
[vflow] 2023/01/11 09:25:29 rcvd sflow data from: 10.1.1.93:6343, size: 772 bytes
[vflow] 2023/01/11 09:25:29 rcvd sflow data from: 10.1.1.93:6343, size: 628 bytes
[vflow] 2023/01/11 09:25:29 rcvd sflow data from: 10.1.1.93:6343, size: 328 bytes
[vflow] 2023/01/11 09:25:30 rcvd sflow data from: 10.1.1.93:6343, size: 800 bytes
[vflow] 2023/01/11 09:25:30 rcvd sflow data from: 10.1.1.93:6343, size: 500 bytes
[vflow] 2023/01/11 09:25:30 kafka: client has run out of available brokers to talk to (Is your cluster reachable?)
[root@l15-96-p-pbs ~]#

vflow config file is :

[root@l15-96-p-pbs vflow]# more /etc/vflow/vflow.conf
verbose: true
ipfix-enabled: false
sflow-workers: 300
sflow-topic: vflow_sflow
netflow5-enabled: false
netflow9-enabled: false
mq-name: kafka
log-file: /var/log/vflow.log

mq config file is :
[root@l15-96-p-pbs vflow]# more /etc/vflow/mq.conf
brokers:
- 10.168.133.127:9092
- 10.168.133.168:9092
- 10.168.133.175:9092
retry-max: 1
retry-backoff: 10

sasl-username: liushilin
sasl-password: sdfawegfsgv

I confirm that the username, password, brokers' ip and port are correct,
what shall I do? thank you_