{"id":471,"date":"2024-09-22T12:13:39","date_gmt":"2024-09-22T12:13:39","guid":{"rendered":"https:\/\/www.erodewebhosting.com\/knowledgebase\/?p=471"},"modified":"2024-09-22T12:16:36","modified_gmt":"2024-09-22T12:16:36","slug":"fix-common-nameserver-errors","status":"publish","type":"post","link":"https:\/\/www.erodewebhosting.com\/knowledgebase\/fix-common-nameserver-errors\/","title":{"rendered":"How to Fix Common Nameserver Errors"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Nameserver errors can disrupt the accessibility of websites and are often a common issue in <a href=\"https:\/\/www.erodewebhosting.com\/shared-web-hosting\/\">web hosting<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Nameserver errors can cause issues with accessing websites, email, and other internet services. Here are some common nameserver errors and how to fix them:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"common-nameserver-errors\">Common Nameserver Errors<\/h3>\n\n\n\n<div class=\"wp-block-rank-math-toc-block\" id=\"rank-math-toc\"><h2>Table of Contents<\/h2><nav><ul><li><a href=\"#common-nameserver-errors\">Common Nameserver Errors<\/a><\/li><li><a href=\"#1-nameserver-not-responding\">1. Nameserver Not Responding<\/a><\/li><li><a href=\"#2-dns-server-not-found\">2. DNS Server Not Found<\/a><\/li><li><a href=\"#3-servfail-error\">3. SERVFAIL Error<\/a><\/li><li><a href=\"#4-refused-error\">4. REFUSED Error<\/a><\/li><li><a href=\"#5-nxdomain-error-non-existent-domain\">5. NXDOMAIN Error (Non-Existent Domain)<\/a><\/li><li><a href=\"#6-timeout-error\">6. Timeout Error<\/a><\/li><li><a href=\"#7-misconfigured-ptr-record-reverse-dns\">7. Misconfigured PTR Record (Reverse DNS)<\/a><\/li><li><a href=\"#8-soa-record-issues\">8. SOA Record Issues<\/a><\/li><li><a href=\"#9-excessive-ttl-time-to-live\">9. Excessive TTL (Time to Live)<\/a><\/li><li><a href=\"#10-looping-or-cyclic-cname-records\">10. Looping or Cyclic CNAME Records<\/a><\/li><li><a href=\"#tools-for-troubleshooting-dns-issues\">Tools for Troubleshooting DNS Issues:<\/a><\/li><\/ul><\/nav><\/div>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"1-nameserver-not-responding\">1. <strong>Nameserver Not Responding<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: DNS query fails because the nameserver doesn\u2019t respond.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Incorrect DNS settings<\/li>\n\n\n\n<li>Firewall or network issues<\/li>\n\n\n\n<li>Outdated cache<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Check DNS Settings<\/strong>: Ensure that the correct nameserver addresses are configured on the client or server.<\/li>\n\n\n\n<li><strong>Flush DNS Cache<\/strong>: Clear the DNS cache to remove outdated information.\n<ul class=\"wp-block-list\">\n<li>Windows: <code>ipconfig \/flushdns<\/code><\/li>\n\n\n\n<li>macOS\/Linux: <code>sudo dscacheutil -flushcache<\/code> or <code>sudo systemd-resolve --flush-caches<\/code><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Test Nameserver Connectivity<\/strong>: Use tools like <code>nslookup<\/code>, <code>dig<\/code>, or <code>ping<\/code> to verify if the nameserver can be reached.<\/li>\n\n\n\n<li><strong>Disable Firewall<\/strong>: Temporarily disable any firewalls or security software to check if they are blocking DNS traffic.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"2-dns-server-not-found\">2. <strong>DNS Server Not Found<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: Browser cannot resolve the domain name because it can\u2019t find the DNS server.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Incorrect or missing DNS records<\/li>\n\n\n\n<li>Issues with the nameserver configuration<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Verify DNS Records<\/strong>: Check if the DNS records (A, MX, CNAME, etc.) are correctly set up in the DNS zone file.<\/li>\n\n\n\n<li><strong>Check Nameserver Configuration<\/strong>: Ensure that the nameservers listed for the domain in the registrar\u2019s settings match the ones configured on the DNS hosting platform.<\/li>\n\n\n\n<li><strong>DNS Propagation<\/strong>: If you recently updated DNS settings, it may take time (up to 48 hours) to propagate. <\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"3-servfail-error\">3. <strong>SERVFAIL Error<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: The DNS query fails due to an internal nameserver problem.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Misconfigured DNSSEC<\/li>\n\n\n\n<li>Recursive query failure<\/li>\n\n\n\n<li>Timeout issues<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Disable or Fix DNSSEC<\/strong>: If DNSSEC is enabled but improperly configured, you may get SERVFAIL. Check the DNSSEC setup in your domain settings or disable it if it\u2019s not needed.<\/li>\n\n\n\n<li><strong>Increase Query Timeout<\/strong>: Modify the DNS resolver\u2019s timeout settings to allow more time for responses.<\/li>\n\n\n\n<li><strong>Recursive DNS Check<\/strong>: Ensure that recursive queries are allowed if necessary, and your server can communicate with upstream DNS servers.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"4-refused-error\">4. <strong>REFUSED Error<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: The DNS server refuses to answer the query.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Misconfigured permissions on the DNS server<\/li>\n\n\n\n<li>Access restrictions or IP filtering<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Allow Queries<\/strong>: Check the DNS server configuration (e.g., <code>named.conf<\/code> for BIND) to ensure that it allows queries from the correct IP addresses or networks.<\/li>\n\n\n\n<li><strong>Check ACLs<\/strong>: Ensure that there are no access control lists (ACLs) preventing queries from being accepted.<\/li>\n\n\n\n<li><strong>Restart DNS Server<\/strong>: Sometimes, restarting the DNS service (BIND, Unbound, etc.) can resolve temporary issues.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"5-nxdomain-error-non-existent-domain\">5. <strong>NXDOMAIN Error (Non-Existent Domain)<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: DNS lookup fails because the domain doesn\u2019t exist.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Domain has expired or was never registered<\/li>\n\n\n\n<li>DNS record is missing or misconfigured<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Check Domain Registration<\/strong>: Ensure the domain is properly registered and hasn\u2019t expired.<\/li>\n\n\n\n<li><strong>Verify DNS Records<\/strong>: Use a DNS lookup tool to see if the correct DNS records are present. If not, add or correct the DNS records in the DNS zone file.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"6-timeout-error\">6. <strong>Timeout Error<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: DNS queries take too long to resolve, resulting in a timeout.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Network congestion or high latency<\/li>\n\n\n\n<li>DNS server is overloaded or down<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Change DNS Server<\/strong>: Switch to a more reliable DNS provider like Google Public DNS (<code>8.8.8.8<\/code>, <code>8.8.4.4<\/code>) or Cloudflare DNS (<code>1.1.1.1<\/code>).<\/li>\n\n\n\n<li><strong>Check DNS Server Load<\/strong>: Ensure that the DNS server isn\u2019t overwhelmed by too many requests. Consider load balancing or reducing the TTL (Time to Live) for certain records.<\/li>\n\n\n\n<li><strong>Optimize Network Connection<\/strong>: Check for network issues, such as packet loss or latency, that may be causing the timeouts.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"7-misconfigured-ptr-record-reverse-dns\">7. <strong>Misconfigured PTR Record (Reverse DNS)<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: Reverse DNS lookups fail, often affecting services like email.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Incorrect or missing PTR record for the server\u2019s IP address<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Configure PTR Record<\/strong>: Contact your <a href=\"https:\/\/www.squarebrothers.com\/web-hosting-india\/\" target=\"_blank\" rel=\"noopener\">hosting provider<\/a> or IP block owner to set up the correct PTR record that matches your server\u2019s hostname.<\/li>\n\n\n\n<li><strong>Verify PTR Record<\/strong>: Use tools like <code>dig<\/code> or <code>nslookup<\/code> to check if the reverse DNS record is correctly configured.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"8-soa-record-issues\">8. <strong>SOA Record Issues<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: Issues with the Start of Authority (SOA) record, often related to DNS zone transfers.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Misconfigured SOA record in the zone file<\/li>\n\n\n\n<li>Mismatched serial numbers between primary and secondary DNS servers<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Check SOA Configuration<\/strong>: Ensure the SOA record is correctly formatted with the proper serial number, refresh interval, retry time, and expiration time.<\/li>\n\n\n\n<li><strong>Update Serial Number<\/strong>: If you have multiple nameservers, ensure the serial number is updated whenever changes are made, so secondary nameservers can sync properly.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"9-excessive-ttl-time-to-live\">9. <strong>Excessive TTL (Time to Live)<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: Cached DNS records stay around too long, causing stale data.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>TTL set too high, leading to slow propagation of updates.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Lower TTL Values<\/strong>: Temporarily reduce the TTL in your DNS records (e.g., from 24 hours to 5 minutes) before making critical updates to ensure quicker propagation. Raise it back up afterward.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"10-looping-or-cyclic-cname-records\">10. <strong>Looping or Cyclic CNAME Records<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Error<\/strong>: CNAME record points to itself or results in a loop.<\/li>\n\n\n\n<li><strong>Causes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Incorrect CNAME setup where a record points back to itself.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Fix<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Check CNAME Records<\/strong>: Ensure that no CNAME record points to another CNAME in a loop. Each CNAME should resolve to an A or AAAA record (an IP address) eventually.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"tools-for-troubleshooting-dns-issues\">Tools for Troubleshooting DNS Issues:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong><code>nslookup<\/code><\/strong>: Simple DNS query tool available on most platforms.<\/li>\n\n\n\n<li><strong><code>dig<\/code><\/strong>: Advanced DNS lookup tool for detailed queries and testing DNS propagation.<\/li>\n\n\n\n<li><strong><code>ping<\/code><\/strong>: To test the connectivity to a server.<\/li>\n\n\n\n<li><strong>Online Tools<\/strong>: DNS propagation tools (e.g., WhatsMyDNS) help track global DNS resolution and verify configuration.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">By following these steps and troubleshooting the common nameserver errors, you can resolve DNS-related issues effectively.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4o<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Nameserver errors can disrupt the accessibility of websites and are often a common issue in web hosting. Nameserver errors can cause issues with accessing websites, email, and other internet services.&hellip;<\/p>\n","protected":false},"author":1,"featured_media":475,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[76],"tags":[],"class_list":["post-471","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-common-nameserver-errors"],"_links":{"self":[{"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/posts\/471","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/comments?post=471"}],"version-history":[{"count":1,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/posts\/471\/revisions"}],"predecessor-version":[{"id":474,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/posts\/471\/revisions\/474"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/media\/475"}],"wp:attachment":[{"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/media?parent=471"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/categories?post=471"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.erodewebhosting.com\/knowledgebase\/wp-json\/wp\/v2\/tags?post=471"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}