[Method]Dynamic IP for your app's A record
As you know,you can’t use MX record once your use CNAME for your root domain,you need the A record.but your app will be in trouble once Openshift update and your app’s IP will change if you use the A record.So we need the dynamic ip address for our A record.i will show you my method,step by step.
1) We need the dns.he.net ‘s Dynamic DNS Service.open an account and transfer your nameserver to dns.he.net.add the A record.choose ‘Enable entry for dynamic dns’ and save,then you will see an icon on the right,cick it to generate a DDNS key and save.for example,my key is ‘iloveopenshit’,my domain is http://123.com. dns.he.net offer a link to autodetect IP address: http://[your domain name]:[your password]@dyn.dns.he.net/nic/update?hostname=[your domain name]
2) Add CARTRIDGE Cron 1.4 for your APP,then upload a cron job script to minutely or hourly or daily or weekly or monthly. IP address gets regularly updated through the cron job script run from your app's cron.the script is :
#!/bin/bash curl http://123.com:iloveopenshift @dyn.dns.he.net/nic/update?hostname=123.com
Save these code as myappip.sh,upload it to cron job.
That is all.you can use dynamic IP for A record and MX record for your domain Email now.Hope it can help some people.Thanks and sorry my poor English.