DNS Spy
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Connectivity: 100%
The following nameservers are available and responding correctly for DNS queries for your domain a21.cz.
| Nameserver | IP address(es) | SOA serial |
|---|---|---|
| ns.forpsi.cz. |
81.2.209.185
2001:15e8:201:1::d1b9 |
2025061301 |
| ns.forpsi.it. |
95.110.254.165
2a00:6d41:2:1::5 |
2025061301 |
| ns.forpsi.net. |
81.2.194.130
2001:15e8:101:1::c282 |
2025061301 |
Good news, no warnings or errors were found.
We could not find any recommendations at this time.
Good news, we detected the following achievements in your DNS configuration. Each of these checks has increased your DNS Spy score.
- All nameservers reply with the same SOA serial number.
- The nameserver IPs are distributed across multiple subnets.
- All nameservers are online.
- Nameservers are available over IPv4.
- Nameservers are available over IPv6.
Performance: 100%
We tested each nameserver and measured the following response times.
| Nameserver | IP address(es) | Response time |
|---|---|---|
| ns.forpsi.cz. |
81.2.209.185
2001:15e8:201:1::d1b9 |
103ms
1ms |
| ns.forpsi.it. |
95.110.254.165
2a00:6d41:2:1::5 |
1ms
1ms |
| ns.forpsi.net. |
81.2.194.130
2001:15e8:101:1::c282 |
1ms
1ms |
Good news, no warnings or errors were found.
We detected some possible recommendations for you to consider. No penalties were given for these, but resolving them can give you a higher DNS score.
- Nameserver ns.forpsi.cz. (81.2.209.185) replied reasonably fast (< 150ms), but you should aim for < 50ms response times.
Good news, we detected the following achievements in your DNS configuration. Each of these checks has increased your DNS Spy score.
- Nameserver ns.forpsi.cz. (2001:15e8:201:1::d1b9) replied in a reasonable time.
- Nameserver ns.forpsi.it. (95.110.254.165) replied quickly (< 50ms).
- Nameserver ns.forpsi.it. (2a00:6d41:2:1::5) replied in a reasonable time.
- Nameserver ns.forpsi.net. (81.2.194.130) replied quickly (< 50ms).
- Nameserver ns.forpsi.net. (2001:15e8:101:1::c282) replied in a reasonable time.
Resilience & Security: 100%
These are the locations and providers of your nameservers.
| Nameserver | Location | ISP |
|---|---|---|
| ns.forpsi.cz. |
IPv4: CZ
IPv6: CZ |
AS24806 - INTERNET-CZ Ktis 2, 384 03 Ktis, CZ
AS24806 - INTERNET-CZ Ktis 2, 384 03 Ktis, CZ |
| ns.forpsi.it. |
IPv4: IT
IPv6: IT |
AS31034 - ARUBA-ASN, IT
AS31034 - ARUBA-ASN, IT |
| ns.forpsi.net. |
IPv4: CZ
IPv6: CZ |
AS24806 - INTERNET-CZ Ktis 2, 384 03 Ktis, CZ
AS24806 - INTERNET-CZ Ktis 2, 384 03 Ktis, CZ |
Good news, no warnings or errors were found.
We detected some possible recommendations for you to consider. No penalties were given for these, but resolving them can give you a higher DNS score.
- No CAA records found. Consider adding CAA records, as it adds increased security by limiting which Certificate Authorities can issue certificates for this domain. (more info)
Good news, we detected the following achievements in your DNS configuration. Each of these checks has increased your DNS Spy score.
- You have more than 1 nameserver.
- The IPv4 nameservers are distributed among multiple providers.
- The IPv4 nameservers are distributed across multiple locations.
- The IPv6 nameservers are distributed among multiple providers.
- The IPv6 nameservers are distributed across multiple locations.
- DNSSEC is enabled.
- The nameservers are being operated from multiple domains (forpsi.cz, forpsi.it, forpsi.net).
DNS records: 100%
Our scans detected the following publicly available DNS records.
| Record | TTL | Value | |
|---|---|---|---|
| A | a21.cz | 1800s | 95.168.196.12 |
| DNSKEY | a21.cz | 1h |
UNKNOWN | UNKNOWN | DNSKEY 256 3 10 AwEAAaK1UIHsiitY1EjvKDca8j61Gx+Cd6vqiI8daM5UqvYekWmwMcx44eo2EnSwPefuKB284WM4+WM4fdtmi51thFCr1rsuYAtTfGRB0Q2pYs2jAdXV5/tIteYmFVc02hwDEkoXIG479VuHpYmq7syehzb9kHpqetX7oz9UjTPUdQST UNKNOWN | UNKNOWN | DNSKEY 257 3 10 AwEAAcHrr29CNGmILo209l52ElewxPErw7PQxHj9tmFFkCY71BqXwoiLtG1LR0sORkZNpO+2Ns37zZ+cRxCseEhLjgC0gSNrlFT9TtDKFr2dDgBbvtPJeKQJf86jPZ7j9K+PrknPbkhOvAIJXviinmgjyuCzYb17dPV/avyXQZz97Hql3XKSsWLbEJKgS82GL8vEO8TBpGkylWI0k1FWx0wQ27+hFqH/AthBwAHbNBq8CKG+u+5HYlICpQCkCFf5Fj2YdLVwLizPe5+IbEFrGYAXyv/6OVGBE0/8VcsAqlduRr8d09X42feoQhM28UWwDFbnb31uMM4g4HejxyHDy1IcrnM= |
| MX | a21.cz | 1h |
0 a21-cz.mail.protection.outlook.com. 32767 ms62389230.msv1.invalid. |
| NS | a21.cz | 1h |
ns.forpsi.cz. ns.forpsi.it. ns.forpsi.net. |
| SOA | a21.cz | 1h | ns.forpsi.net. admin.forpsi.com. 2025061301 14400 3600 2592000 3600 |
| TXT | a21.cz | 1h |
"facebook-domain-verification=7qlpije91ca7z296a4lqydb5na2pnc" "google-site-verification=tb-CJgktUf_7JiKY0xI1MVae4C_kg3RMh73MzcIH9JA" "v=spf1 ip4:82.86.110.15 include:spf.protection.outlook.com include:smtpx.stable.cz ~all" |
| TXT | _amazonses.a21.cz | 1h |
"facebook-domain-verification=7qlpije91ca7z296a4lqydb5na2pnc" "google-site-verification=tb-CJgktUf_7JiKY0xI1MVae4C_kg3RMh73MzcIH9JA" "v=spf1 ip4:82.86.110.15 include:spf.protection.outlook.com include:smtpx.stable.cz ~all" |
| CNAME | _dmarc.a21.cz | 1800s | a21.cz |
| TXT | _dmarc.a21.cz | 1h |
"facebook-domain-verification=7qlpije91ca7z296a4lqydb5na2pnc" "google-site-verification=tb-CJgktUf_7JiKY0xI1MVae4C_kg3RMh73MzcIH9JA" "v=spf1 ip4:82.86.110.15 include:spf.protection.outlook.com include:smtpx.stable.cz ~all" |
| SRV | _sip._tls.a21.cz | 1800s | 100 1 443 sipdir.online.lync.com. |
| SRV | _sipfederationtls._tcp.a21.cz | 1800s | 100 1 5061 sipfed.online.lync.com. |
| CNAME | admin.a21.cz | 1800s | a21.cz |
| CNAME | administration.a21.cz | 1800s | a21.cz |
| CNAME | ads.a21.cz | 1800s | a21.cz |
| CNAME | adserver.a21.cz | 1800s | a21.cz |
| CNAME | alerts.a21.cz | 1800s | a21.cz |
| CNAME | alpha.a21.cz | 1800s | a21.cz |
| CNAME | analytics.a21.cz | 1800s | a21.cz |
| CNAME | ap.a21.cz | 1800s | a21.cz |
| CNAME | apache.a21.cz | 1800s | a21.cz |
| TXT | api.a21.cz | 1h |
"facebook-domain-verification=7qlpije91ca7z296a4lqydb5na2pnc" "google-site-verification=tb-CJgktUf_7JiKY0xI1MVae4C_kg3RMh73MzcIH9JA" "v=spf1 ip4:82.86.110.15 include:spf.protection.outlook.com include:smtpx.stable.cz ~all" |
| CNAME | app.a21.cz | 1800s | a21.cz |
| CNAME | apps.a21.cz | 1800s | a21.cz |
| CNAME | appserver.a21.cz | 1800s | a21.cz |
| CNAME | auth.a21.cz | 1800s | a21.cz |
| CNAME | autodiscover.a21.cz | 1h | autodiscover.outlook.com |
| CNAME | backup.a21.cz | 1800s | a21.cz |
| CNAME | beta.a21.cz | 1800s | a21.cz |
| CNAME | blog.a21.cz | 1800s | a21.cz |
| CNAME | calendar.a21.cz | 1800s | a21.cz |
| CNAME | cdn.a21.cz | 1800s | a21.cz |
| CNAME | chat.a21.cz | 1800s | a21.cz |
| CNAME | citrix.a21.cz | 1800s | a21.cz |
| CNAME | clients.a21.cz | 1800s | a21.cz |
| CNAME | cms.a21.cz | 1800s | a21.cz |
| CNAME | confluence.a21.cz | 1800s | a21.cz |
| CNAME | corp.a21.cz | 1800s | a21.cz |
| CNAME | cpanel.a21.cz | 1800s | a21.cz |
| CNAME | crs.a21.cz | 1800s | a21.cz |
| CNAME | cvs.a21.cz | 1800s | a21.cz |
| CNAME | database.a21.cz | 1800s | a21.cz |
| CNAME | db.a21.cz | 1800s | a21.cz |
| TXT | default.a21.cz | 1h |
"facebook-domain-verification=7qlpije91ca7z296a4lqydb5na2pnc" "google-site-verification=tb-CJgktUf_7JiKY0xI1MVae4C_kg3RMh73MzcIH9JA" "v=spf1 ip4:82.86.110.15 include:spf.protection.outlook.com include:smtpx.stable.cz ~all" |
| CNAME | demo.a21.cz | 1800s | a21.cz |
| CNAME | dev.a21.cz | 1800s | a21.cz |
| CNAME | devel.a21.cz | 1800s | a21.cz |
| CNAME | development.a21.cz | 1800s | a21.cz |
| CNAME | devsql.a21.cz | 1800s | a21.cz |
| CNAME | dhcp.a21.cz | 1800s | a21.cz |
| CNAME | direct.a21.cz | 1800s | a21.cz |
| CNAME | dmz.a21.cz | 1800s | a21.cz |
| CNAME | dns.a21.cz | 1800s | a21.cz |
| CNAME | dns0.a21.cz | 1800s | a21.cz |
| CNAME | dns00.a21.cz | 1800s | a21.cz |
| CNAME | dns01.a21.cz | 1800s | a21.cz |
| CNAME | dns010.a21.cz | 1800s | a21.cz |
| CNAME | dns02.a21.cz | 1800s | a21.cz |
| CNAME | dns03.a21.cz | 1800s | a21.cz |
| CNAME | dns04.a21.cz | 1800s | a21.cz |
| CNAME | dns05.a21.cz | 1800s | a21.cz |
| CNAME | dns06.a21.cz | 1800s | a21.cz |
| CNAME | dns07.a21.cz | 1800s | a21.cz |
| CNAME | dns08.a21.cz | 1800s | a21.cz |
| CNAME | dns09.a21.cz | 1800s | a21.cz |
| CNAME | dns1.a21.cz | 1800s | a21.cz |
| CNAME | dns10.a21.cz | 1800s | a21.cz |
| CNAME | dns2.a21.cz | 1800s | a21.cz |
| CNAME | dns3.a21.cz | 1800s | a21.cz |
| CNAME | dns4.a21.cz | 1800s | a21.cz |
| CNAME | dns5.a21.cz | 1800s | a21.cz |
| CNAME | dns6.a21.cz | 1800s | a21.cz |
| CNAME | dns7.a21.cz | 1800s | a21.cz |
| CNAME | dns8.a21.cz | 1800s | a21.cz |
| CNAME | dns9.a21.cz | 1800s | a21.cz |
| CNAME | download.a21.cz | 1800s | a21.cz |
| CNAME | em0.a21.cz | 1800s | a21.cz |
| CNAME | em00.a21.cz | 1800s | a21.cz |
| CNAME | em01.a21.cz | 1800s | a21.cz |
| CNAME | em010.a21.cz | 1800s | a21.cz |
| CNAME | em02.a21.cz | 1800s | a21.cz |
| CNAME | em03.a21.cz | 1800s | a21.cz |
| CNAME | em04.a21.cz | 1800s | a21.cz |
| CNAME | em05.a21.cz | 1800s | a21.cz |
| CNAME | em06.a21.cz | 1800s | a21.cz |
| CNAME | em07.a21.cz | 1800s | a21.cz |
| CNAME | em08.a21.cz | 1800s | a21.cz |
| CNAME | em09.a21.cz | 1800s | a21.cz |
| CNAME | em1.a21.cz | 1800s | a21.cz |
| CNAME | em10.a21.cz | 1800s | a21.cz |
| CNAME | em2.a21.cz | 1800s | a21.cz |
| CNAME | em3.a21.cz | 1800s | a21.cz |
| CNAME | em4.a21.cz | 1800s | a21.cz |
| CNAME | em5.a21.cz | 1800s | a21.cz |
| CNAME | em6.a21.cz | 1800s | a21.cz |
| CNAME | em7.a21.cz | 1800s | a21.cz |
| CNAME | em8.a21.cz | 1800s | a21.cz |
| CNAME | em9.a21.cz | 1800s | a21.cz |
| CNAME | emergency.a21.cz | 1800s | a21.cz |
| CNAME | en.a21.cz | 1800s | a21.cz |
| CNAME | enterpriseenrollment.a21.cz | 1h | enterpriseenrollment.manage.microsoft.com |
| CNAME | enterpriseregistration.a21.cz | 1h | enterpriseregistration.windows.net |
| CNAME | erp.a21.cz | 1800s | a21.cz |
| CNAME | eshop.a21.cz | 1800s | a21.cz |
| CNAME | exchange.a21.cz | 1800s | a21.cz |
| CNAME | f5.a21.cz | 1800s | a21.cz |
| CNAME | fileserver.a21.cz | 1800s | a21.cz |
| CNAME | firewall.a21.cz | 1800s | a21.cz |
| CNAME | forum.a21.cz | 1800s | a21.cz |
| CNAME | ftp.a21.cz | 1800s | a21.cz |
| CNAME | gateway.a21.cz | 1800s | a21.cz |
| CNAME | gc._msdcs.a21.cz | 1800s | a21.cz |
| CNAME | git.a21.cz | 1800s | a21.cz |
| CNAME | gw.a21.cz | 1800s | a21.cz |
| CNAME | help.a21.cz | 1800s | a21.cz |
| CNAME | home.a21.cz | 1800s | a21.cz |
| CNAME | host.a21.cz | 1800s | a21.cz |
| CNAME | http.a21.cz | 1800s | a21.cz |
| CNAME | id.a21.cz | 1800s | a21.cz |
| CNAME | images.a21.cz | 1800s | a21.cz |
| CNAME | imap.a21.cz | 1800s | imap.forpsi.com |
| CNAME | imap4.a21.cz | 1800s | a21.cz |
| CNAME | info.a21.cz | 1800s | a21.cz |
| CNAME | internal.a21.cz | 1800s | a21.cz |
| CNAME | internet.a21.cz | 1800s | a21.cz |
| CNAME | intranet.a21.cz | 1800s | a21.cz |
| CNAME | ipv4.a21.cz | 1800s | a21.cz |
| CNAME | ipv6.a21.cz | 1800s | a21.cz |
| CNAME | jenkins.a21.cz | 1800s | a21.cz |
| CNAME | jira.a21.cz | 1800s | a21.cz |
| CNAME | lab.a21.cz | 1800s | a21.cz |
| CNAME | lb0.a21.cz | 1800s | a21.cz |
| CNAME | lb00.a21.cz | 1800s | a21.cz |
| CNAME | lb01.a21.cz | 1800s | a21.cz |
| CNAME | lb010.a21.cz | 1800s | a21.cz |
| CNAME | lb02.a21.cz | 1800s | a21.cz |
| CNAME | lb03.a21.cz | 1800s | a21.cz |
| CNAME | lb04.a21.cz | 1800s | a21.cz |
| CNAME | lb05.a21.cz | 1800s | a21.cz |
| CNAME | lb06.a21.cz | 1800s | a21.cz |
| CNAME | lb07.a21.cz | 1800s | a21.cz |
| CNAME | lb08.a21.cz | 1800s | a21.cz |
| CNAME | lb09.a21.cz | 1800s | a21.cz |
| CNAME | lb1.a21.cz | 1800s | a21.cz |
| CNAME | lb10.a21.cz | 1800s | a21.cz |
| CNAME | lb2.a21.cz | 1800s | a21.cz |
| CNAME | lb3.a21.cz | 1800s | a21.cz |
| CNAME | lb4.a21.cz | 1800s | a21.cz |
| CNAME | lb5.a21.cz | 1800s | a21.cz |
| CNAME | lb6.a21.cz | 1800s | a21.cz |
| CNAME | lb7.a21.cz | 1800s | a21.cz |
| CNAME | lb8.a21.cz | 1800s | a21.cz |
| CNAME | lb9.a21.cz | 1800s | a21.cz |
| CNAME | ldap.a21.cz | 1800s | a21.cz |
| CNAME | linux.a21.cz | 1800s | a21.cz |
| CNAME | local.a21.cz | 1800s | a21.cz |
| CNAME | localhost.a21.cz | 1800s | a21.cz |
| CNAME | log.a21.cz | 1800s | a21.cz |
| CNAME | lyncdiscover.a21.cz | 1h | webdir.online.lync.com |
| CNAME | mail.a21.cz | 1800s | a21.cz |
| CNAME | mail0.a21.cz | 1800s | a21.cz |
| CNAME | mail00.a21.cz | 1800s | a21.cz |
| CNAME | mail01.a21.cz | 1800s | a21.cz |
| CNAME | mail010.a21.cz | 1800s | a21.cz |
| CNAME | mail02.a21.cz | 1800s | a21.cz |
| CNAME | mail03.a21.cz | 1800s | a21.cz |
| CNAME | mail04.a21.cz | 1800s | a21.cz |
| CNAME | mail05.a21.cz | 1800s | a21.cz |
| CNAME | mail06.a21.cz | 1800s | a21.cz |
| CNAME | mail07.a21.cz | 1800s | a21.cz |
| CNAME | mail08.a21.cz | 1800s | a21.cz |
| CNAME | mail09.a21.cz | 1800s | a21.cz |
| CNAME | mail1.a21.cz | 1800s | a21.cz |
| CNAME | mail10.a21.cz | 1800s | a21.cz |
| CNAME | mail2.a21.cz | 1800s | a21.cz |
| CNAME | mail3.a21.cz | 1800s | a21.cz |
| CNAME | mail4.a21.cz | 1800s | a21.cz |
| CNAME | mail5.a21.cz | 1800s | a21.cz |
| CNAME | mail6.a21.cz | 1800s | a21.cz |
| CNAME | mail7.a21.cz | 1800s | a21.cz |
| CNAME | mail8.a21.cz | 1800s | a21.cz |
| CNAME | mail9.a21.cz | 1800s | a21.cz |
| CNAME | mailgate.a21.cz | 1800s | a21.cz |
| CNAME | mailing.a21.cz | 1800s | a21.cz |
| TXT | mailjet.a21.cz | 1h |
"facebook-domain-verification=7qlpije91ca7z296a4lqydb5na2pnc" "google-site-verification=tb-CJgktUf_7JiKY0xI1MVae4C_kg3RMh73MzcIH9JA" "v=spf1 ip4:82.86.110.15 include:spf.protection.outlook.com include:smtpx.stable.cz ~all" |
| CNAME | main.a21.cz | 1800s | a21.cz |
| CNAME | manage.a21.cz | 1800s | a21.cz |
| CNAME | mgmt.a21.cz | 1800s | a21.cz |
| CNAME | mirror.a21.cz | 1800s | a21.cz |
| CNAME | mobile.a21.cz | 1800s | a21.cz |
| CNAME | monitor.a21.cz | 1800s | a21.cz |
| CNAME | msoid.a21.cz | 1h | clientconfig.microsoftonline-p.net |
| CNAME | mssql.a21.cz | 1800s | a21.cz |
| CNAME | mta.a21.cz | 1800s | a21.cz |
| CNAME | mx.a21.cz | 1800s | a21.cz |
| CNAME | mx0.a21.cz | 1800s | a21.cz |
| CNAME | mx00.a21.cz | 1800s | a21.cz |
| CNAME | mx01.a21.cz | 1800s | a21.cz |
| CNAME | mx010.a21.cz | 1800s | a21.cz |
| CNAME | mx02.a21.cz | 1800s | a21.cz |
| CNAME | mx03.a21.cz | 1800s | a21.cz |
| CNAME | mx04.a21.cz | 1800s | a21.cz |
| CNAME | mx05.a21.cz | 1800s | a21.cz |
| CNAME | mx06.a21.cz | 1800s | a21.cz |
| CNAME | mx07.a21.cz | 1800s | a21.cz |
| CNAME | mx08.a21.cz | 1800s | a21.cz |
| CNAME | mx09.a21.cz | 1800s | a21.cz |
| CNAME | mx1.a21.cz | 1800s | a21.cz |
| CNAME | mx10.a21.cz | 1800s | a21.cz |
| CNAME | mx2.a21.cz | 1800s | a21.cz |
| CNAME | mx3.a21.cz | 1800s | a21.cz |
| CNAME | mx4.a21.cz | 1800s | a21.cz |
| CNAME | mx5.a21.cz | 1800s | a21.cz |
| CNAME | mx6.a21.cz | 1800s | a21.cz |
| CNAME | mx7.a21.cz | 1800s | a21.cz |
| CNAME | mx8.a21.cz | 1800s | a21.cz |
| CNAME | mx9.a21.cz | 1800s | a21.cz |
| CNAME | mysql.a21.cz | 1800s | a21.cz |
| CNAME | mysql-master.a21.cz | 1800s | a21.cz |
| CNAME | mysql-slave.a21.cz | 1800s | a21.cz |
| CNAME | new.a21.cz | 1800s | a21.cz |
| CNAME | news.a21.cz | 1800s | a21.cz |
| CNAME | noc.a21.cz | 1800s | a21.cz |
| CNAME | ns.a21.cz | 1800s | a21.cz |
| CNAME | ns0.a21.cz | 1800s | a21.cz |
| CNAME | ns00.a21.cz | 1800s | a21.cz |
| CNAME | ns01.a21.cz | 1800s | a21.cz |
| CNAME | ns010.a21.cz | 1800s | a21.cz |
| CNAME | ns02.a21.cz | 1800s | a21.cz |
| CNAME | ns03.a21.cz | 1800s | a21.cz |
| CNAME | ns04.a21.cz | 1800s | a21.cz |
| CNAME | ns05.a21.cz | 1800s | a21.cz |
| CNAME | ns06.a21.cz | 1800s | a21.cz |
| CNAME | ns07.a21.cz | 1800s | a21.cz |
| CNAME | ns08.a21.cz | 1800s | a21.cz |
| CNAME | ns09.a21.cz | 1800s | a21.cz |
| CNAME | ns1.a21.cz | 1800s | a21.cz |
| CNAME | ns10.a21.cz | 1800s | a21.cz |
| CNAME | ns2.a21.cz | 1800s | a21.cz |
| CNAME | ns3.a21.cz | 1800s | a21.cz |
| CNAME | ns4.a21.cz | 1800s | a21.cz |
| CNAME | ns5.a21.cz | 1800s | a21.cz |
| CNAME | ns6.a21.cz | 1800s | a21.cz |
| CNAME | ns7.a21.cz | 1800s | a21.cz |
| CNAME | ns8.a21.cz | 1800s | a21.cz |
| CNAME | ns9.a21.cz | 1800s | a21.cz |
| CNAME | ntp.a21.cz | 1800s | a21.cz |
| CNAME | office.a21.cz | 1800s | a21.cz |
| CNAME | ops.a21.cz | 1800s | a21.cz |
| CNAME | oracle.a21.cz | 1800s | a21.cz |
| CNAME | owa.a21.cz | 1800s | a21.cz |
| CNAME | pbx.a21.cz | 1800s | a21.cz |
| CNAME | piwik.a21.cz | 1800s | a21.cz |
| CNAME | pop.a21.cz | 1800s | a21.cz |
| CNAME | pop3.a21.cz | 1800s | pop3.forpsi.com |
| CNAME | preprod.a21.cz | 1800s | a21.cz |
| CNAME | prod.a21.cz | 1800s | a21.cz |
| CNAME | production.a21.cz | 1800s | a21.cz |
| CNAME | projects.a21.cz | 1800s | a21.cz |
| CNAME | rdp.a21.cz | 1800s | a21.cz |
| CNAME | remote.a21.cz | 1800s | a21.cz |
| CNAME | robot.a21.cz | 1800s | a21.cz |
| CNAME | safe.a21.cz | 1800s | a21.cz |
| CNAME | secure.a21.cz | 1800s | a21.cz |
| CNAME | server.a21.cz | 1800s | a21.cz |
| CNAME | shop.a21.cz | 1800s | a21.cz |
| CNAME | sip.a21.cz | 1h | sipdir.online.lync.com |
| CNAME | smtp.a21.cz | 1800s | smtpa.forpsi.com |
| CNAME | sql.a21.cz | 1800s | a21.cz |
| CNAME | sql0.a21.cz | 1800s | a21.cz |
| CNAME | sql00.a21.cz | 1800s | a21.cz |
| CNAME | sql01.a21.cz | 1800s | a21.cz |
| CNAME | sql010.a21.cz | 1800s | a21.cz |
| CNAME | sql02.a21.cz | 1800s | a21.cz |
| CNAME | sql03.a21.cz | 1800s | a21.cz |
| CNAME | sql04.a21.cz | 1800s | a21.cz |
| CNAME | sql05.a21.cz | 1800s | a21.cz |
| CNAME | sql06.a21.cz | 1800s | a21.cz |
| CNAME | sql07.a21.cz | 1800s | a21.cz |
| CNAME | sql08.a21.cz | 1800s | a21.cz |
| CNAME | sql09.a21.cz | 1800s | a21.cz |
| CNAME | sql1.a21.cz | 1800s | a21.cz |
| CNAME | sql10.a21.cz | 1800s | a21.cz |
| CNAME | sql2.a21.cz | 1800s | a21.cz |
| CNAME | sql3.a21.cz | 1800s | a21.cz |
| CNAME | sql4.a21.cz | 1800s | a21.cz |
| CNAME | sql5.a21.cz | 1800s | a21.cz |
| CNAME | sql6.a21.cz | 1800s | a21.cz |
| CNAME | sql7.a21.cz | 1800s | a21.cz |
| CNAME | sql8.a21.cz | 1800s | a21.cz |
| CNAME | sql9.a21.cz | 1800s | a21.cz |
| CNAME | squid.a21.cz | 1800s | a21.cz |
| CNAME | ssh.a21.cz | 1800s | a21.cz |
| CNAME | ssl.a21.cz | 1800s | a21.cz |
| CNAME | stage.a21.cz | 1800s | a21.cz |
| CNAME | staging.a21.cz | 1800s | a21.cz |
| CNAME | stats.a21.cz | 1800s | a21.cz |
| CNAME | support.a21.cz | 1800s | a21.cz |
| CNAME | svn.a21.cz | 1800s | a21.cz |
| CNAME | syslog.a21.cz | 1800s | a21.cz |
| CNAME | test.a21.cz | 1800s | a21.cz |
| CNAME | testing.a21.cz | 1800s | a21.cz |
| CNAME | tracking.a21.cz | 1800s | a21.cz |
| CNAME | upload.a21.cz | 1800s | a21.cz |
| CNAME | val.a21.cz | 1800s | a21.cz |
| CNAME | vm.a21.cz | 1800s | a21.cz |
| CNAME | vnc.a21.cz | 1800s | a21.cz |
| CNAME | voip.a21.cz | 1800s | a21.cz |
| CNAME | vpn.a21.cz | 1800s | a21.cz |
| CNAME | web0.a21.cz | 1800s | a21.cz |
| CNAME | web00.a21.cz | 1800s | a21.cz |
| CNAME | web01.a21.cz | 1800s | a21.cz |
| CNAME | web010.a21.cz | 1800s | a21.cz |
| CNAME | web02.a21.cz | 1800s | a21.cz |
| CNAME | web03.a21.cz | 1800s | a21.cz |
| CNAME | web04.a21.cz | 1800s | a21.cz |
| CNAME | web05.a21.cz | 1800s | a21.cz |
| CNAME | web06.a21.cz | 1800s | a21.cz |
| CNAME | web07.a21.cz | 1800s | a21.cz |
| CNAME | web08.a21.cz | 1800s | a21.cz |
| CNAME | web09.a21.cz | 1800s | a21.cz |
| CNAME | web1.a21.cz | 1800s | a21.cz |
| CNAME | web10.a21.cz | 1800s | a21.cz |
| CNAME | web2.a21.cz | 1800s | a21.cz |
| CNAME | web3.a21.cz | 1800s | a21.cz |
| CNAME | web4.a21.cz | 1800s | a21.cz |
| CNAME | web5.a21.cz | 1800s | a21.cz |
| CNAME | web6.a21.cz | 1800s | a21.cz |
| CNAME | web7.a21.cz | 1800s | a21.cz |
| CNAME | web8.a21.cz | 1800s | a21.cz |
| CNAME | web9.a21.cz | 1800s | a21.cz |
| CNAME | webdisk.a21.cz | 1800s | a21.cz |
| CNAME | webmail.a21.cz | 1800s | webmail.forpsi.com |
| CNAME | webshop.a21.cz | 1800s | a21.cz |
| CNAME | whois.a21.cz | 1800s | a21.cz |
| CNAME | wiki.a21.cz | 1800s | a21.cz |
| CNAME | www.a21.cz | 1800s | a21.cz. |
| CNAME | xml.a21.cz | 1800s | xml.ck.cz |
Good news, no warnings or errors were found.
We detected some possible recommendations for you to consider. No penalties were given for these, but resolving them can give you a higher DNS score.
- No DMARC records have been found. Consider configuring DMARC for improved e-mail authentication.
- No IPv6 record has been found on the zone apex (a21.cz). Consider enabling IPv6 in the infrastructure by adding an AAAA record on this domain.
Good news, we detected the following achievements in your DNS configuration. Each of these checks has increased your DNS Spy score.
- Multiple MX records found.
- MX records with different priorities found (main + fall-back mailservers).
- The MX record for "a21.cz" has a long TTL (1h+).
- The MX records points to multiple mailservers.
- The NS records have a long TTL (1h+).
- Your SOA serial number follows the best practice YYYYMMDDxx format.
- SPF records have been found.
- SPF records are set up restrictively.
- Found a root (apex) DNS record.
- Found a www DNS record.
- The active nameservers match the NS records.
- The DNS records appear to be RFC compliant.
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