Two nodes can't connect, but `consul rtt` reports estimated time of milliseconds

#### Overview of the Issue

Consul rtt command gives estimated times between two hosts that its logs show cannot connect. Test scenario: the Consul server(s) are all in network A, but hosts are in networks A, B, and C. And while B and C can communicate with A, they cannot communicate with each other. Yet `consul rtt` between hosts in networks B and C shows an estimated connection time of milliseconds:

```
[auto@b-httpd-02 ~]$ consul rtt c-httpd-06
Estimated c-httpd-06 <-> b-httpd-02 rtt: 0.296 ms (using LAN coordinates)
```

---

#### Reproduction Steps

Test scenario: the Consul server(s) are all in network A, but hosts are in networks A, B, and C. And while B and C can communicate with A, they cannot communicate with each other.

You can tell what network each node is on by the first letter in the name designation in the following list:

```
Node Address Status Type Build Protocol DC Partition Segment
a-consul-01 192.168.20.3:8301 alive server 1.18.1 2 dca default
a-httpd-03 192.168.20.16:8301 alive client 1.18.1 2 dca default
a-httpd-04 192.168.20.18:8301 alive client 1.18.1 2 dca default
a-httpd-08 192.168.20.22:8301 alive client 1.18.1 2 dca default
a-httpd-11 192.168.20.25:8301 alive client 1.18.1 2 dca default
a-httpd-13 192.168.20.27:8301 alive client 1.18.1 2 dca default
b-httpd-02 192.168.20.80:8301 alive client 1.18.1 2 dca default
b-httpd-04 192.168.20.82:8301 alive client 1.18.1 2 dca default
b-httpd-06 192.168.20.84:8301 alive client 1.18.1 2 dca default
b-httpd-08 192.168.20.86:8301 alive client 1.18.1 2 dca default
c-httpd-02 192.168.20.144:8301 alive client 1.18.1 2 dca default
c-httpd-04 192.168.20.146:8301 alive client 1.18.1 2 dca default
c-httpd-05 192.168.20.147:8301 alive client 1.18.1 2 dca default
c-httpd-06 192.168.20.148:8301 alive client 1.18.1 2 dca default
```

Logs demonstrate Consul clients cannot connect between networks B and C:

```
[auto@b-httpd-02 ~]$ consul monitor c-httpd-02 --debug
2024-04-04T13:49:19.994-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-02 has failed, no acks received
2024-04-04T13:49:31.469-0500 [ERROR] agent.client.memberlist.lan: memberlist: Push/Pull with c-httpd-05 failed: dial tcp 192.168.20.147:8301: i/o timeout
2024-04-04T13:49:37.995-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-05 has failed, no acks received
2024-04-04T13:49:43.994-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-04 has failed, no acks received
2024-04-04T13:49:47.995-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-06 has failed, no acks received
2024-04-04T13:49:56.531-0500 [WARN] agent.client.memberlist.lan: memberlist: Refuting a suspect message (from: c-httpd-04)
```

Yet querying the RTT between hosts in B and C yields an estimated time like the following:

```
[auto@b-httpd-02 ~]$ consul rtt c-httpd-06
Estimated c-httpd-06 <-> b-httpd-02 rtt: 0.296 ms (using LAN coordinates)
```

### Consul info for both Client and Server

Client info

```
Output from client 'consul info' command here
```

```
[auto@b-httpd-02 ~]$ consul info
agent:
check_monitors = 0
check_ttls = 0
checks = 1
services = 1
build:
prerelease =
revision = 98cb473c
version = 1.18.1
version_metadata =
consul:
acl = disabled
known_servers = 1
server = false
runtime:
arch = amd64
cpu_count = 1
goroutines = 52
max_procs = 1
os = linux
version = go1.21.8
serf_lan:
coordinate_resets = 0
encrypted = false
event_queue = 0
event_time = 6
failed = 0
health_score = 0
intent_queue = 0
left = 0
member_time = 17
members = 14
query_queue = 0
query_time = 1
```

```
Client agent HCL config
```

Server info

```
Output from server 'consul info' command here
```

```
[root@a-consul-01 ~]# consul info
agent:
check_monitors = 0
check_ttls = 0
checks = 0
services = 0
build:
prerelease =
revision = 98cb473c
version = 1.18.1
version_metadata =
consul:
acl = disabled
bootstrap = true
known_datacenters = 1
leader = true
leader_addr = 192.168.20.3:8300
server = true
raft:
applied_index = 19333
commit_index = 19333
fsm_pending = 0
last_contact = 0
last_log_index = 19333
last_log_term = 3
last_snapshot_index = 16390
last_snapshot_term = 3
latest_configuration = [{Suffrage:Voter ID:2535d27a-b261-5c06-f925-98f0a080decf Address:192.168.20.3:8300}]
latest_configuration_index = 0
num_peers = 0
protocol_version = 3
protocol_version_max = 3
protocol_version_min = 0
snapshot_version_max = 1
snapshot_version_min = 0
state = Leader
term = 3
runtime:
arch = amd64
cpu_count = 2
goroutines = 322
max_procs = 2
os = linux
version = go1.21.8
serf_lan:
coordinate_resets = 0
encrypted = false
event_queue = 0
event_time = 6
failed = 0
health_score = 0
intent_queue = 0
left = 0
member_time = 17
members = 14
query_queue = 0
query_time = 1
serf_wan:
coordinate_resets = 0
encrypted = false
event_queue = 0
event_time = 1
failed = 0
health_score = 0
intent_queue = 0
left = 0
member_time = 1
members = 1
query_queue = 0
query_time = 1
```

```
Server agent HCL config
```

### Operating system and Environment details

### Log Fragments

```
[auto@b-httpd-02 ~]$ consul monitor c-httpd-02 --debug
2024-04-04T13:49:19.994-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-02 has failed, no acks received
2024-04-04T13:49:31.469-0500 [ERROR] agent.client.memberlist.lan: memberlist: Push/Pull with c-httpd-05 failed: dial tcp 192.168.20.147:8301: i/o timeout
2024-04-04T13:49:37.995-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-05 has failed, no acks received
2024-04-04T13:49:43.994-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-04 has failed, no acks received
2024-04-04T13:49:47.995-0500 [INFO] agent.client.memberlist.lan: memberlist: Suspect c-httpd-06 has failed, no acks received
2024-04-04T13:49:56.531-0500 [WARN] agent.client.memberlist.lan: memberlist: Refuting a suspect message (from: c-httpd-04)
```

Start by reproducing the reported `consul rtt` result in the described network A/B/C topology and compare it with the memberlist timeout logs. Trace the `consul rtt` command and LAN coordinate behavior to determine whether the estimate reflects reachability; done means the behavior is corrected or its limitation is explicitly covered by tests or documentation.

Written by the indexing model from the issue text.