너는 개발자냐?

[sendmail] Relaying denied. IP name lookup failed

step 1.

vi  /etc/mail/access

Connect:192.168.0.1                      RELAY

#접속할 IP 추가

메일 서버에 접속할  ip 추가 후 저장

step 2

/usr/sbin/makemap hash /etc/mail/access < /etc/mail/access

바로 적용 됨.

java 에서 사용할 네트웍 관련 메서드들...

공인IP가져오기, 

IP 검증 등

package common.util;

import java.io.IOException;

import java.io.InputStream;

import java.net.URL;

import java.net.URLConnection;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import java.util.regex.PatternSyntaxException;

import javax.net.ssl.HostnameVerifier;

import javax.net.ssl.HttpsURLConnection;

import javax.net.ssl.SSLContext;

import javax.net.ssl.SSLSession;

import javax.net.ssl.TrustManager;

import javax.net.ssl.X509TrustManager;

public class NewtorkUtil {

public static void main(String[] args) {

System.out.println(ipToLong("192.168.0"));

}

private static Pattern VALID_IPV4_PATTERN = null;

private static Pattern VALID_IPV6_PATTERN = null;

private static final String ipv4Pattern = "(([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.){3}([01]?\\d\\d?|2[0-4]\\d|25[0-5])";

private static final String ipv6Pattern = "([0-9a-f]{1,4}:){7}([0-9a-f]){1,4}";

static {

try {

VALID_IPV4_PATTERN = Pattern.compile(ipv4Pattern, Pattern.CASE_INSENSITIVE);

VALID_IPV6_PATTERN = Pattern.compile(ipv6Pattern, Pattern.CASE_INSENSITIVE);

} catch (PatternSyntaxException e) {

// logger.severe("Unable to compile pattern", e);

}

}

/**

* IP Address 검증

* @param ipAddress

* @return

*/

public static boolean isIpAddress(String ipAddress) {

Matcher m1 = VALID_IPV4_PATTERN.matcher(ipAddress);

if (m1.matches()) {

return true;

}

Matcher m2 = VALID_IPV6_PATTERN.matcher(ipAddress);

return m2.matches();

}

/**

* IP 값 롱타입으로 변환

* 

* @param ipAddress

* @return

*/

public static long ipToLong(String ipAddress) {

long result = 0;

if (isIpAddress(ipAddress)) {

String[] ipAddressInArray = ipAddress.split("\\.");

for (int i = 0; i < ipAddressInArray.length; i++) {

int power = 3 - i;

int ip = Integer.parseInt(ipAddressInArray[i]);

result += ip * Math.pow(256, power);

}

}

return result;

}

/**

* 공인 IP 가져오기 AWS API 사용해서 가져오기

* 

* @return

*/

public static String getPublicIP() {

String result = null;

try {

String sUrl = "http://checkip.amazonaws.com/";

URL url = new URL(sUrl);

URLConnection clsConn = getConnection(url);

InputStream is = clsConn.getInputStream();

java.io.BufferedReader reader = new java.io.BufferedReader(new java.io.InputStreamReader(is));

result = reader.readLine();

} catch (Exception ex) {

ex.printStackTrace();

}

return result;

}

public static URLConnection getConnection(URL url) {

URLConnection conn = null;

HttpsURLConnection https = null;

try {

if (url.getProtocol().toLowerCase().equals("https")) {

trustAllHosts();

https = (HttpsURLConnection) url.openConnection();

https.setHostnameVerifier(DO_NOT_VERIFY);

conn = https;

} else {

conn = url.openConnection();

}

} catch (IOException e) {

e.printStackTrace();

}

return conn;

}

final static HostnameVerifier DO_NOT_VERIFY = new HostnameVerifier() {

@Override

public boolean verify(String hostname, SSLSession session) {

return true;

}

};

private static void trustAllHosts() {

// Create a trust manager that does not validate certificate chains

TrustManager[] trustAllCerts = new TrustManager[] { new X509TrustManager() {

@Override

public java.security.cert.X509Certificate[] getAcceptedIssuers() {

return new java.security.cert.X509Certificate[] {};

}

@Override

public void checkClientTrusted(java.security.cert.X509Certificate[] chain, String authType) {

}

@Override

public void checkServerTrusted(java.security.cert.X509Certificate[] chain, String authType) {

}

} };

// Install the all-trusting trust manager

try {

SSLContext sc = SSLContext.getInstance("TLS");

sc.init(null, trustAllCerts, new java.security.SecureRandom());

HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());

} catch (Exception e) {

e.printStackTrace();

}

}

}