最近一臺電腦突然系統崩潰了，想做個新增節點的實驗。由於之前裝的都是ubuntu作業系統，於是想選個異構的REDHAT試試。

在試驗第一步，裝了個Redis進行看看，才發現遠端無法訪問，以前由於都裝了有SSH，能輕鬆訪問。而這回出現的錯誤是：Could not connect to Redis at 192.168.2.195:6379: No route to host

這個問題以前還真沒遇到過。網上一查，才發現是新裝系統設定的iptables問題。

於是設定

iptables -N REDIS
iptables -A REDIS -s 192.168.10.1 -j ACCEPT
iptables -A REDIS -s 192.168.10.2 -j ACCEPT
iptables -A REDIS -j LOG --log-prefix "unauth-redis-access"
iptables -A REDIS -j REJECT --reject-with icmp-port-unreachable
iptables -I INPUT -p tcp --dport 6379 -j REDIS
 

或者

sudo iptables -F

輕鬆解決。

如下測試：

[email protected]:/usr/local/bin$ redis-cli -h "192.168.2.195" -p 6379
Could not connect to Redis at 192.168.2.195:6379: No route to host
not connected> quit
[email protected]:/usr/local/bin$ redis-cli -h "192.168.2.195" -p 6379
Could not connect to Redis at 192.168.2.195:6379: No route to host
not connected> quit

[email protected]:/usr/local/bin$ redis-cli -h "192.168.2.195" -p 6379
192.168.2.195:6379> select 10
(error) NOAUTH Authentication required.
192.168.2.195:6379> quit
[email protected]:/usr/local/bin$ redis-cli -h 192.168.2.195 -p 6379 -a ndscndscndsc
192.168.2.195:6379> select 10
OK
192.168.2.195:6379[10]> keys *
1) "189234234"
2) "123"
192.168.2.195:6379[10]>