How to list NATS servers on TAS

Products

• VMware Tanzu Application Service for VMs

Issue/Introduction

Starting in nats release v46 the underlying package nats-server has been updated from v1 to v2. This change has been introduced in the following TAS versions:

• TAS v2.11.26+
• TAS v2.13.14+
• TAS v3.0+
• TAS v4.0+
• TAS v5.0+

NATS is running as part of NATS-wrapper process that performs migration from NATS v1 to NATS v2 during an applicable TAS upgrade. As part of this process it connects to all NATS servers to validate they are all running before switching them all to v2 to avoid split brain. NATS wrappers connect to NATS servers to get their version until they migrate them.

Environment

Product Version: 4.0

Resolution

The list of NATS servers will be in clusters -> urls under /varz endpoint. You can run bosh -d <YOUR-CF-DEPLOYMENT> ssh nats -c "curl localhost:8222/varz" to get it: 

% bosh -d <YOUR-CF-DEPLOYMENT> ssh nats -c "curl localhost:8222/varz"
Using environment '10.225.28.129' as client 'ops_manager'
Using deployment 'cf-1631c63accc0c5ca075c'
Task 16797. Done
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stderr | Unauthorized use is strictly prohibited. All access and activity
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stderr | is subject to logging and monitoring.
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout | {
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "server_id": "NCLOJFUOHO7K53JCSZZMKL7YZZ5RPOCJ7VDNH24KKIPP34NRJ27ADGVL",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "server_name": "NCLOJFUOHO7K53JCSZZMKL7YZZ5RPOCJ7VDNH24KKIPP34NRJ27ADGVL",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "version": "2.8.4",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "proto": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "go": "go1.20.1",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "host": "10.225.28.130",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "port": 4222,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "auth_required": true,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "max_connections": 65536,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "ping_interval": 120000000000,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "ping_max": 2,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "http_host": "0.0.0.0",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "http_port": 8222,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "http_base_path": "",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "https_port": 0,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "auth_timeout": 15,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "max_control_line": 4096,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "max_payload": 1048576,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "max_pending": 67108864,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "cluster": {
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "name": "rAZBwVAtuLQ5YMiCrzxcYi",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "addr": "10.225.28.130",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "cluster_port": 4223,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "auth_timeout": 15,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "urls": [
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |       "8b0bcd10-b7ae-4daa-aac7-1d142bdf430f.nats.service.cf.internal:4223",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |       "8b0bcd10-b7ae-4daa-aac7-1d142bdf430f.nats.service.cf.internal:4225"
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     ],
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "tls_timeout": 5,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "tls_required": true,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "tls_verify": true
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   },
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "gateway": {},
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "leaf": {},
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "mqtt": {},
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "websocket": {},
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "jetstream": {},
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "tls_timeout": 2,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "write_deadline": 2000000000,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "start": "2024-02-23T20:34:45.991343863Z",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "now": "2024-03-20T07:14:15.418455781Z",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "uptime": "25d10h39m29s",
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "mem": 23498752,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "cores": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "gomaxprocs": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "cpu": 0,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "connections": 15,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "total_connections": 219517,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "routes": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "remotes": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "leafnodes": 0,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "in_msgs": 7942278,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "out_msgs": 7942281,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "in_bytes": 5133499927,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "out_bytes": 5133500347,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "slow_consumers": 0,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "subscriptions": 10,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "http_req_stats": {
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "/": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "/connz": 1,
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |     "/varz": 2
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   },
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout |   "config_load_time": "2024-02-23T20:34:45.991343863Z"
nats/8b0bcd10-b7ae-4daa-aac7-1d142bdf430f: stdout | }Connection to 10.225.28.130 closed.
Succeeded