How to check if a RBL server is working and given IP address is listed in it?
You can customise the pre defined RBL servers in MailScan Antispam configuration and / or Raspop configuration. To check if particular RBL server is working and given IP address is listed in it, just follow the steps given below.
Pre-requisite:
- Windows operating system.
- That system should have direct internet connection.
- Nslookup utility
- Open Command prompt.
- Type nslookup and press enter
- Then type following command
Server 8.8.8.8
Press enter
- Then type following command
Press enter
5. Then reverse the IP Address on which you want to run the test i.e. check if the IP is black listed
e.g. if you have IP address to check 121.246.72.71 reverse will look like 71.72.246.121; type command as 71.72.246.121.bl.spamcop.net
You can see Address: field which gives ip address called 127.0.0.2, it indicates that the particular ip for which we queried is listed in the bl.spamcop.net.
6. If RBL server is working but Ip address is not listed then it will show below output
It says “non-existent domain” it means the entry for that IP is not present on the RBL server.
7. If you want to check if particular RBL server is exist or not run the same command as above
You can see the above output where it says “Server Failed” it means RBL server is not responding. You can remove that server from the RBL check so that your mail flow timing will improve.
In addition to above, w ecan even check using PING command.
To check if IP 121.246.72.71 is listed in bl.spamcop.net, ping in reverse order:
# ping 71.72.246.121.bl.spamcop.net
Pinging 71.72.246.121.bl.spamcop.net [127.0.0.2] with 32 bytes of data:
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
If the ip is not listed then the return message will be:
Unknown host:
Some of the Return Code and its description as given below:
Return Code Zone Description
127.0.0.2 SBL Spamhaus SBL Data
127.0.0.3 SBL Spamhaus SBL CSS Data
127.0.0.4 XBL CBL Data
127.0.0.5 XBL Customized NJABL Data
127.0.0.10 PBL ISP Maintained
127.0.0.11 PBL Spamhaus Maintained
Spamhaus uses this general convention for return codes:
Return Code Description
127.0.0.0/24 Spamhaus IP Blocklists
127.0.1.0/24 Spamhaus Domain Blocklists
127.0.2.0/24 Spamhaus Whitelists
Comment of Sachin R:
From command line execute this command and you will get the result as 127.0.0.2 / 127.0.0.1 : ping 71.72.246.121.bl.spamcop.net
Added at: 2012-06-30 12:46