Email infrastructure of upol.cz
According to Live Direct Marketing's daily DNS scan (September 7, 2026), upol.cz (Tranco rank #21,533) points its inbound MX to Unknown / Other and authorizes SmartEmailing in SPF. Its observed DMARC policy is p=none (monitoring). Policy alone does not establish inbox or spam placement.
Last updated: .
| Mailbox provider (MX) | Unknown / Other |
|---|---|
| ESPs in SPF | SmartEmailing |
| SaaS senders in SPF | none detected |
| DMARC policy | p=none |
| DMARC record | v=DMARC1; p=none; rua=mailto:dmarc+664774@smartemailing.cz; fo=1 |
| Tranco rank | #21,533 |
| Snapshot | 2026-09-07 (updated daily) |
Keep an eye on upol.cz
Get a first health report, then meaningful changes to SPF, DMARC, MX, sampled MX PTR and blocklists. See your domain history and run a real inbox placement test from your private watchlist.
Manage existing subscriptions →How upol.cz compares
Same daily dataset, three views: how its mailbox provider is trending, how strict DMARC is at its position in the list, and where its own policy sits among all DMARC publishers in the dataset.
Market share of Unknown / Other
DMARC enforced by list position
Policy maturity of all DMARC publishers
From observation to a useful check
- What was observed
- The DNS records and classifications in this snapshot.
- What it means
- MX describes inbound mail; SPF authorizes senders.
- What is unknown
- The actual sending IP, nested SPF dependencies, inbox placement and commercial relationships. MTA-STS, TLS-RPT and BIMI adoption are not measured.
- Next check
- Verify current DNS and test a real message: run an inbox placement test.
DNS records
Source: OpenINTEL / Tranco. Capture: 2026-09-07. These are answers from the measurement vantage point, not a live DNS check. TTL is the observed cache lifetime in seconds.
upol.cz · A — Answer records observed
IPv4 addresses for this name. They do not identify the mail server or prove a hosting migration.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- upol.cz · A · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
158.194.230.160 - upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=00a71acf94d0b72d417fcda9e812e211d36b733d7bf4579e56a7a5cca9dd69a12300d1e5d214a5cac5bd4f582be79118cf141bb10b5c84bd73fbed07a6cf640b; signature_expiration=1790842993; signature_inception=1788249243; signer_name=upol.cz.; type_covered=A
upol.cz · AAAA — Unknown: no conclusive answer in this capture
IPv6 addresses for this name. An address record does not test service availability.
upol.cz · NS — Answer records observed
Name servers listed for the DNS zone.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- upol.cz · NS · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
namer2.upol.cz. - upol.cz · NS · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
nsa.ces.net. - upol.cz · NS · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
raven.upol.cz. - upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=2a917efef6abdbf1724a9398861a49494fc0a7d2d75a8b271e9949e2578f986c9d296cd9ceb72cad75bb840b380251f8c7f15393456f1049dfa64f562096a421; signature_expiration=1790844646; signature_inception=1788252612; signer_name=upol.cz.; type_covered=NS
upol.cz · MX — Answer records observed
Servers named to receive mail. Lower preference numbers are tried first.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- upol.cz · MX · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
12801 ax.virusfree.cz. - upol.cz · MX · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
12817 bx.virusfree.cz. - upol.cz · MX · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
12833 cx.spamfree.cz. - upol.cz · MX · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
12849 dx.spamfree.cz. - upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=3c81d27754897c438e1ac81c4596ce893c8e57acd80dcc1f7f0428a0f3c405e0bd8db0ee41816914366455e5177603bdac6761a4ddf960affc73cd7dc3a6193e; signature_expiration=1790493168; signature_inception=1787898704; signer_name=upol.cz.; type_covered=MX
upol.cz · SOA — Answer records observed
Zone administration data. The serial is a version number, not a creation date or clock.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=99b96622b027b0e032fd0af168fbf79a19190079d1923a83686e986ed4720b594ea7fbad93d22a6920175fec7e8520618a3dee17fff5dc3259286f40c02384fc; signature_expiration=1791330025; signature_inception=1788734425; signer_name=upol.cz.; type_covered=SOA - upol.cz · SOA · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
expire=3600000; minimum=86400; mname=raven.upol.cz.; refresh=900; retry=1800; rname=petv.cvt.upol.cz.; serial=2260902245
upol.cz · CAA — Unknown: no conclusive answer in this capture
Rules for certificate issuance. These do not show whether an existing certificate is valid.
upol.cz · TXT — Answer records observed
Text records can publish mail policies, domain-control challenges or other data.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=749b239c6bf5b1d5b35c8733c8e4f76e6bb3c2829e31a96e9a12df8690bc589d0ef87fce35048e5d8533fa70609f491360e1a86d2ff5711b9518b9d76443f85a; signature_expiration=1790376242; signature_inception=1787781441; signer_name=upol.cz.; type_covered=TXT Other TXT data; its purpose is not established by this measurement.
Raw TXT value
upol.cz · TXT · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0"3zNARbt6ooYOB+Lzg3XaA39D3JeK4QmZ+FyeRVi9ST64p23zqvAdD8E3UVnBfWw6pa9N7/Wr8OquNBLFV+/o9Q=="Domain-control verification for Google; not proof of active SaaS or mail use.
Raw TXT value
upol.cz · TXT · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0"google-site-verification=qJolb0krHwEuAaY3OknP03vj90vAw_uLnaQtyEMhzJo"SPF: authorized mail senders; not proof that mail was sent.
Raw TXT value
upol.cz · TXT · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0"v=spf1 include:_spf.google.com include:spf.protection.outlook.com ip4:158.194.0.0/16 ip6:2001:718:1401::/48 include:spf.smartemailing.cz include:spf.olc.cz ~all"
upol.cz · DNSKEY — Answer records observed
DNSSEC key, signature or denial-of-existence data observed in this response.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- upol.cz · DNSKEY · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; flags=257; pk_eccgost_x=0357c0c78f748d46f10688a3b6f4375954061fa96761870bf3eb232af90311fa; pk_eccgost_y=0da1f4b9554985d1861c366d712482e854f77323c0e9d71407ead331b978c7c4; protocol=3 - upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=e66812643a73d9ff376ce70502bd63c92dc914c4b89f9be03e44c00b8aaa98f270a46257398a599e1b271e7189e8a7c102fc8313567dc3999e206063cfe07f6e; signature_expiration=1790847259; signature_inception=1788254529; signer_name=upol.cz.; type_covered=DNSKEY
upol.cz · DS — Unknown: no conclusive answer in this capture
DNSSEC key, signature or denial-of-existence data observed in this response.
upol.cz · CDS — Unknown: no conclusive answer in this capture
DNSSEC key, signature or denial-of-existence data observed in this response.
upol.cz · CDNSKEY — Unknown: no conclusive answer in this capture
DNSSEC key, signature or denial-of-existence data observed in this response.
www.upol.cz · A — Answer records observed
IPv4 addresses for this name. They do not identify the mail server or prove a hosting migration.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- tonus4-f5.upol.cz · A · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
158.194.230.160 - tonus4-f5.upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=11f8a0c7c95674af80c3ed1a3b93bb66a07206bc6190811de64dcd1567babb4b7976d6c9908e60ed0c766e0e9dfc5f97e52435006283bfdeee37484cbf0163d5; signature_expiration=1790841591; signature_inception=1788249477; signer_name=upol.cz.; type_covered=A - www.upol.cz · CNAME · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
tonus4-f5.upol.cz. - www.upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz.; type_covered=CNAME
www.upol.cz · AAAA — Answer records observed
IPv6 addresses for this name. An address record does not test service availability.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- www.upol.cz · CNAME · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
tonus4-f5.upol.cz. - www.upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz.; type_covered=CNAME
_dmarc.upol.cz · TXT — Answer records observed
Text records can publish mail policies, domain-control challenges or other data.
Query observed at: 2026-09-07T00:11:30Z.
Response code: 0.
- _dmarc.upol.cz · RRSIG · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=3f34801de99f620bc5e36e85b6a0143bf6e064216d774c2cbc4a750ad9122be0c2bd882c28fef5d40f96d0465d6d18e87c4621a40bb0678f420aeba7f4307f3d; signature_expiration=1790181304; signature_inception=1787587702; signer_name=upol.cz.; type_covered=TXT DMARC: published handling and reporting policy for authentication failures.
Raw TXT value
_dmarc.upol.cz · TXT · TTL 86400 s · 2026-09-07T00:11:30Z · AD=0"v=DMARC1; p=none; rua=mailto:dmarc+664774@smartemailing.cz; fo=1"
DNSSEC records are shown only when returned. An unset AD flag is not proof that a zone is unsigned. MTA-STS, TLS-RPT, BIMI and arbitrary DKIM selectors are not measured here; their absence cannot be inferred.
Recorded DNS history
Registry presence: first seen 2026-04-28; last seen 2026-09-07. These are appearances in our domain registry, not domain registration dates or earlier DNS values.
This history starts with saved RR captures. Provider market-share charts are aggregate context, not this domain’s DNS history. Dates identify observations; no continuous validity between them is implied. Equivalent RR states are combined, ignoring response TTL and capture-time changes. Up to 30 distinct RR states and 60 dated captures are retained within a per-domain byte limit.
Recent observed differences
2026-09-05 → 2026-09-07
_dmarc.upol.cz · TXT
Before: 2026-09-05 — Answer records observed
- _dmarc.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=f47b6e011038803931c799b443acbcbaeff69180a8af9871de4fc87601ee82d90d0fc94493edfb58aa6cf5f69201052d8f2e5612bb071f6319574fba7e0f6672; signature_expiration=1790167281; signature_inception=1787572578; signer_name=upol.cz; type_covered=TXT DMARC: published handling and reporting policy for authentication failures.
Raw TXT value
_dmarc.upol.cz · TXT"v=DMARC1; p=none; rua=mailto:dmarc+664774@smartemailing.cz; fo=1"
After: 2026-09-07 — Answer records observed
- _dmarc.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=3f34801de99f620bc5e36e85b6a0143bf6e064216d774c2cbc4a750ad9122be0c2bd882c28fef5d40f96d0465d6d18e87c4621a40bb0678f420aeba7f4307f3d; signature_expiration=1790181304; signature_inception=1787587702; signer_name=upol.cz; type_covered=TXT DMARC: published handling and reporting policy for authentication failures.
Raw TXT value
_dmarc.upol.cz · TXT"v=DMARC1; p=none; rua=mailto:dmarc+664774@smartemailing.cz; fo=1"
upol.cz · A
Before: 2026-09-05 — Answer records observed
- upol.cz · A
158.194.230.160 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=f7f714da46ceac3f36c7e45e0a5b95770749663f972679de5c1732249a0073f06be5f4c540644c50b11ae5ba5924a6cdffb850cbf9bf53b334621a51d9deec16; signature_expiration=1790852870; signature_inception=1788257505; signer_name=upol.cz; type_covered=A
After: 2026-09-07 — Answer records observed
- upol.cz · A
158.194.230.160 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=00a71acf94d0b72d417fcda9e812e211d36b733d7bf4579e56a7a5cca9dd69a12300d1e5d214a5cac5bd4f582be79118cf141bb10b5c84bd73fbed07a6cf640b; signature_expiration=1790842993; signature_inception=1788249243; signer_name=upol.cz; type_covered=A
upol.cz · DNSKEY
Before: 2026-09-05 — Answer records observed
- upol.cz · DNSKEY
algorithm=13; flags=257; pk_eccgost_x=0357c0c78f748d46f10688a3b6f4375954061fa96761870bf3eb232af90311fa; pk_eccgost_y=0da1f4b9554985d1861c366d712482e854f77323c0e9d71407ead331b978c7c4; protocol=3 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=bb4a6af09c80e61c8fc167681cbf1d2c5f6f9188d9314c3da8725e00e778e11cd17c64ae3e56e06d90123af8922562bee51e102a93d895cedd8c7a7bf91a9f24; signature_expiration=1790846232; signature_inception=1788253335; signer_name=upol.cz; type_covered=DNSKEY
After: 2026-09-07 — Answer records observed
- upol.cz · DNSKEY
algorithm=13; flags=257; pk_eccgost_x=0357c0c78f748d46f10688a3b6f4375954061fa96761870bf3eb232af90311fa; pk_eccgost_y=0da1f4b9554985d1861c366d712482e854f77323c0e9d71407ead331b978c7c4; protocol=3 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=e66812643a73d9ff376ce70502bd63c92dc914c4b89f9be03e44c00b8aaa98f270a46257398a599e1b271e7189e8a7c102fc8313567dc3999e206063cfe07f6e; signature_expiration=1790847259; signature_inception=1788254529; signer_name=upol.cz; type_covered=DNSKEY
upol.cz · MX
Before: 2026-09-05 — Answer records observed
- upol.cz · MX
12801 ax.virusfree.cz - upol.cz · MX
12817 bx.virusfree.cz - upol.cz · MX
12833 cx.spamfree.cz - upol.cz · MX
12849 dx.spamfree.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=eb02b07bedc8406b95b45ff4724c6e1b45b3e9a2a86c65bd307d05bcb1ac4683e9528a02b1c1fd868faa95ae76f4f22c5d4fe7560385d423f803876193008806; signature_expiration=1790490194; signature_inception=1787898067; signer_name=upol.cz; type_covered=MX
After: 2026-09-07 — Answer records observed
- upol.cz · MX
12801 ax.virusfree.cz - upol.cz · MX
12817 bx.virusfree.cz - upol.cz · MX
12833 cx.spamfree.cz - upol.cz · MX
12849 dx.spamfree.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=3c81d27754897c438e1ac81c4596ce893c8e57acd80dcc1f7f0428a0f3c405e0bd8db0ee41816914366455e5177603bdac6761a4ddf960affc73cd7dc3a6193e; signature_expiration=1790493168; signature_inception=1787898704; signer_name=upol.cz; type_covered=MX
upol.cz · NS
Before: 2026-09-05 — Answer records observed
- upol.cz · NS
namer2.upol.cz - upol.cz · NS
nsa.ces.net - upol.cz · NS
raven.upol.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=a904ad24097c219e0ea2d0815aa7f5a84aa491f64893fc74301634110ce6e7ca7a196804efa61407b174dfe1924d358f778a4d2ca0fbcf2efa642b90ed578af2; signature_expiration=1790848925; signature_inception=1788253762; signer_name=upol.cz; type_covered=NS
After: 2026-09-07 — Answer records observed
- upol.cz · NS
namer2.upol.cz - upol.cz · NS
nsa.ces.net - upol.cz · NS
raven.upol.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=2a917efef6abdbf1724a9398861a49494fc0a7d2d75a8b271e9949e2578f986c9d296cd9ceb72cad75bb840b380251f8c7f15393456f1049dfa64f562096a421; signature_expiration=1790844646; signature_inception=1788252612; signer_name=upol.cz; type_covered=NS
upol.cz · SOA
Before: 2026-09-05 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=3f405aa3bf9a22f7f1bb51d9473c14b64049fbbe1551e2c65e7db5e9bdfcdfd94321ebd8008ca86b6c086fe6e63778f910f65f8ba6eecf0ca0806734bfe28804; signature_expiration=1791158722; signature_inception=1788563122; signer_name=upol.cz; type_covered=SOA - upol.cz · SOA
expire=3600000; minimum=86400; mname=raven.upol.cz; refresh=900; retry=1800; rname=petv.cvt.upol.cz; serial=2260903097
After: 2026-09-07 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=99b96622b027b0e032fd0af168fbf79a19190079d1923a83686e986ed4720b594ea7fbad93d22a6920175fec7e8520618a3dee17fff5dc3259286f40c02384fc; signature_expiration=1791330025; signature_inception=1788734425; signer_name=upol.cz; type_covered=SOA - upol.cz · SOA
expire=3600000; minimum=86400; mname=raven.upol.cz; refresh=900; retry=1800; rname=petv.cvt.upol.cz; serial=2260902245
upol.cz · TXT
Before: 2026-09-05 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=8f21ad53d60d00d3ebe514e876ea1ece1dd3bc42bf6a078ca9df597603043c1ac41b7cebf2f6b986bc806b33c5963e08891c314f1abdc2aa78781b146a7e2c0a; signature_expiration=1790379602; signature_inception=1787784950; signer_name=upol.cz; type_covered=TXT Other TXT data; its purpose is not established by this measurement.
Raw TXT value
upol.cz · TXT"3zNARbt6ooYOB+Lzg3XaA39D3JeK4QmZ+FyeRVi9ST64p23zqvAdD8E3UVnBfWw6pa9N7/Wr8OquNBLFV+/o9Q=="Domain-control verification for Google; not proof of active SaaS or mail use.
Raw TXT value
upol.cz · TXT"google-site-verification=qJolb0krHwEuAaY3OknP03vj90vAw_uLnaQtyEMhzJo"SPF: authorized mail senders; not proof that mail was sent.
Raw TXT value
upol.cz · TXT"v=spf1 include:_spf.google.com include:spf.protection.outlook.com ip4:158.194.0.0/16 ip6:2001:718:1401::/48 include:spf.smartemailing.cz include:spf.olc.cz ~all"
After: 2026-09-07 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=749b239c6bf5b1d5b35c8733c8e4f76e6bb3c2829e31a96e9a12df8690bc589d0ef87fce35048e5d8533fa70609f491360e1a86d2ff5711b9518b9d76443f85a; signature_expiration=1790376242; signature_inception=1787781441; signer_name=upol.cz; type_covered=TXT Other TXT data; its purpose is not established by this measurement.
Raw TXT value
upol.cz · TXT"3zNARbt6ooYOB+Lzg3XaA39D3JeK4QmZ+FyeRVi9ST64p23zqvAdD8E3UVnBfWw6pa9N7/Wr8OquNBLFV+/o9Q=="Domain-control verification for Google; not proof of active SaaS or mail use.
Raw TXT value
upol.cz · TXT"google-site-verification=qJolb0krHwEuAaY3OknP03vj90vAw_uLnaQtyEMhzJo"SPF: authorized mail senders; not proof that mail was sent.
Raw TXT value
upol.cz · TXT"v=spf1 include:_spf.google.com include:spf.protection.outlook.com ip4:158.194.0.0/16 ip6:2001:718:1401::/48 include:spf.smartemailing.cz include:spf.olc.cz ~all"
www.upol.cz · A
Before: 2026-09-05 — Answer records observed
- tonus4-f5.upol.cz · A
158.194.230.160 - tonus4-f5.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=d11ba28a1549c577f6ea743ea05d32335498403dc2fbc01e376288fc0e5dbcafc2beafcb390af07700dd62cb3da858a982d557636e72a8e06ad953d28bcece66; signature_expiration=1790836142; signature_inception=1788241624; signer_name=upol.cz; type_covered=A - www.upol.cz · CNAME
tonus4-f5.upol.cz - www.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz; type_covered=CNAME
After: 2026-09-07 — Answer records observed
- tonus4-f5.upol.cz · A
158.194.230.160 - tonus4-f5.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=11f8a0c7c95674af80c3ed1a3b93bb66a07206bc6190811de64dcd1567babb4b7976d6c9908e60ed0c766e0e9dfc5f97e52435006283bfdeee37484cbf0163d5; signature_expiration=1790841591; signature_inception=1788249477; signer_name=upol.cz; type_covered=A - www.upol.cz · CNAME
tonus4-f5.upol.cz - www.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz; type_covered=CNAME
Available saved snapshots
2026-09-07
Each query below keeps its own observation date; unknown checks may retain older values.
_dmarc.upol.cz · TXT
2026-09-07 — Answer records observed
- _dmarc.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=3f34801de99f620bc5e36e85b6a0143bf6e064216d774c2cbc4a750ad9122be0c2bd882c28fef5d40f96d0465d6d18e87c4621a40bb0678f420aeba7f4307f3d; signature_expiration=1790181304; signature_inception=1787587702; signer_name=upol.cz; type_covered=TXT DMARC: published handling and reporting policy for authentication failures.
Raw TXT value
_dmarc.upol.cz · TXT"v=DMARC1; p=none; rua=mailto:dmarc+664774@smartemailing.cz; fo=1"
upol.cz · A
2026-09-07 — Answer records observed
- upol.cz · A
158.194.230.160 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=00a71acf94d0b72d417fcda9e812e211d36b733d7bf4579e56a7a5cca9dd69a12300d1e5d214a5cac5bd4f582be79118cf141bb10b5c84bd73fbed07a6cf640b; signature_expiration=1790842993; signature_inception=1788249243; signer_name=upol.cz; type_covered=A
upol.cz · DNSKEY
2026-09-07 — Answer records observed
- upol.cz · DNSKEY
algorithm=13; flags=257; pk_eccgost_x=0357c0c78f748d46f10688a3b6f4375954061fa96761870bf3eb232af90311fa; pk_eccgost_y=0da1f4b9554985d1861c366d712482e854f77323c0e9d71407ead331b978c7c4; protocol=3 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=e66812643a73d9ff376ce70502bd63c92dc914c4b89f9be03e44c00b8aaa98f270a46257398a599e1b271e7189e8a7c102fc8313567dc3999e206063cfe07f6e; signature_expiration=1790847259; signature_inception=1788254529; signer_name=upol.cz; type_covered=DNSKEY
upol.cz · MX
2026-09-07 — Answer records observed
- upol.cz · MX
12801 ax.virusfree.cz - upol.cz · MX
12817 bx.virusfree.cz - upol.cz · MX
12833 cx.spamfree.cz - upol.cz · MX
12849 dx.spamfree.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=3c81d27754897c438e1ac81c4596ce893c8e57acd80dcc1f7f0428a0f3c405e0bd8db0ee41816914366455e5177603bdac6761a4ddf960affc73cd7dc3a6193e; signature_expiration=1790493168; signature_inception=1787898704; signer_name=upol.cz; type_covered=MX
upol.cz · NS
2026-09-07 — Answer records observed
- upol.cz · NS
namer2.upol.cz - upol.cz · NS
nsa.ces.net - upol.cz · NS
raven.upol.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=2a917efef6abdbf1724a9398861a49494fc0a7d2d75a8b271e9949e2578f986c9d296cd9ceb72cad75bb840b380251f8c7f15393456f1049dfa64f562096a421; signature_expiration=1790844646; signature_inception=1788252612; signer_name=upol.cz; type_covered=NS
upol.cz · SOA
2026-09-07 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=99b96622b027b0e032fd0af168fbf79a19190079d1923a83686e986ed4720b594ea7fbad93d22a6920175fec7e8520618a3dee17fff5dc3259286f40c02384fc; signature_expiration=1791330025; signature_inception=1788734425; signer_name=upol.cz; type_covered=SOA - upol.cz · SOA
expire=3600000; minimum=86400; mname=raven.upol.cz; refresh=900; retry=1800; rname=petv.cvt.upol.cz; serial=2260902245
upol.cz · TXT
2026-09-07 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=749b239c6bf5b1d5b35c8733c8e4f76e6bb3c2829e31a96e9a12df8690bc589d0ef87fce35048e5d8533fa70609f491360e1a86d2ff5711b9518b9d76443f85a; signature_expiration=1790376242; signature_inception=1787781441; signer_name=upol.cz; type_covered=TXT Other TXT data; its purpose is not established by this measurement.
Raw TXT value
upol.cz · TXT"3zNARbt6ooYOB+Lzg3XaA39D3JeK4QmZ+FyeRVi9ST64p23zqvAdD8E3UVnBfWw6pa9N7/Wr8OquNBLFV+/o9Q=="Domain-control verification for Google; not proof of active SaaS or mail use.
Raw TXT value
upol.cz · TXT"google-site-verification=qJolb0krHwEuAaY3OknP03vj90vAw_uLnaQtyEMhzJo"SPF: authorized mail senders; not proof that mail was sent.
Raw TXT value
upol.cz · TXT"v=spf1 include:_spf.google.com include:spf.protection.outlook.com ip4:158.194.0.0/16 ip6:2001:718:1401::/48 include:spf.smartemailing.cz include:spf.olc.cz ~all"
www.upol.cz · A
2026-09-07 — Answer records observed
- tonus4-f5.upol.cz · A
158.194.230.160 - tonus4-f5.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=11f8a0c7c95674af80c3ed1a3b93bb66a07206bc6190811de64dcd1567babb4b7976d6c9908e60ed0c766e0e9dfc5f97e52435006283bfdeee37484cbf0163d5; signature_expiration=1790841591; signature_inception=1788249477; signer_name=upol.cz; type_covered=A - www.upol.cz · CNAME
tonus4-f5.upol.cz - www.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz; type_covered=CNAME
www.upol.cz · AAAA
2026-09-07 — Answer records observed
- www.upol.cz · CNAME
tonus4-f5.upol.cz - www.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz; type_covered=CNAME
2026-09-05
Each query below keeps its own observation date; unknown checks may retain older values.
_dmarc.upol.cz · TXT
2026-09-05 — Answer records observed
- _dmarc.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=f47b6e011038803931c799b443acbcbaeff69180a8af9871de4fc87601ee82d90d0fc94493edfb58aa6cf5f69201052d8f2e5612bb071f6319574fba7e0f6672; signature_expiration=1790167281; signature_inception=1787572578; signer_name=upol.cz; type_covered=TXT DMARC: published handling and reporting policy for authentication failures.
Raw TXT value
_dmarc.upol.cz · TXT"v=DMARC1; p=none; rua=mailto:dmarc+664774@smartemailing.cz; fo=1"
upol.cz · A
2026-09-05 — Answer records observed
- upol.cz · A
158.194.230.160 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=f7f714da46ceac3f36c7e45e0a5b95770749663f972679de5c1732249a0073f06be5f4c540644c50b11ae5ba5924a6cdffb850cbf9bf53b334621a51d9deec16; signature_expiration=1790852870; signature_inception=1788257505; signer_name=upol.cz; type_covered=A
upol.cz · DNSKEY
2026-09-05 — Answer records observed
- upol.cz · DNSKEY
algorithm=13; flags=257; pk_eccgost_x=0357c0c78f748d46f10688a3b6f4375954061fa96761870bf3eb232af90311fa; pk_eccgost_y=0da1f4b9554985d1861c366d712482e854f77323c0e9d71407ead331b978c7c4; protocol=3 - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=bb4a6af09c80e61c8fc167681cbf1d2c5f6f9188d9314c3da8725e00e778e11cd17c64ae3e56e06d90123af8922562bee51e102a93d895cedd8c7a7bf91a9f24; signature_expiration=1790846232; signature_inception=1788253335; signer_name=upol.cz; type_covered=DNSKEY
upol.cz · MX
2026-09-05 — Answer records observed
- upol.cz · MX
12801 ax.virusfree.cz - upol.cz · MX
12817 bx.virusfree.cz - upol.cz · MX
12833 cx.spamfree.cz - upol.cz · MX
12849 dx.spamfree.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=eb02b07bedc8406b95b45ff4724c6e1b45b3e9a2a86c65bd307d05bcb1ac4683e9528a02b1c1fd868faa95ae76f4f22c5d4fe7560385d423f803876193008806; signature_expiration=1790490194; signature_inception=1787898067; signer_name=upol.cz; type_covered=MX
upol.cz · NS
2026-09-05 — Answer records observed
- upol.cz · NS
namer2.upol.cz - upol.cz · NS
nsa.ces.net - upol.cz · NS
raven.upol.cz - upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=a904ad24097c219e0ea2d0815aa7f5a84aa491f64893fc74301634110ce6e7ca7a196804efa61407b174dfe1924d358f778a4d2ca0fbcf2efa642b90ed578af2; signature_expiration=1790848925; signature_inception=1788253762; signer_name=upol.cz; type_covered=NS
upol.cz · SOA
2026-09-05 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=3f405aa3bf9a22f7f1bb51d9473c14b64049fbbe1551e2c65e7db5e9bdfcdfd94321ebd8008ca86b6c086fe6e63778f910f65f8ba6eecf0ca0806734bfe28804; signature_expiration=1791158722; signature_inception=1788563122; signer_name=upol.cz; type_covered=SOA - upol.cz · SOA
expire=3600000; minimum=86400; mname=raven.upol.cz; refresh=900; retry=1800; rname=petv.cvt.upol.cz; serial=2260903097
upol.cz · TXT
2026-09-05 — Answer records observed
- upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=2; original_ttl=86400; signature=8f21ad53d60d00d3ebe514e876ea1ece1dd3bc42bf6a078ca9df597603043c1ac41b7cebf2f6b986bc806b33c5963e08891c314f1abdc2aa78781b146a7e2c0a; signature_expiration=1790379602; signature_inception=1787784950; signer_name=upol.cz; type_covered=TXT Other TXT data; its purpose is not established by this measurement.
Raw TXT value
upol.cz · TXT"3zNARbt6ooYOB+Lzg3XaA39D3JeK4QmZ+FyeRVi9ST64p23zqvAdD8E3UVnBfWw6pa9N7/Wr8OquNBLFV+/o9Q=="Domain-control verification for Google; not proof of active SaaS or mail use.
Raw TXT value
upol.cz · TXT"google-site-verification=qJolb0krHwEuAaY3OknP03vj90vAw_uLnaQtyEMhzJo"SPF: authorized mail senders; not proof that mail was sent.
Raw TXT value
upol.cz · TXT"v=spf1 include:_spf.google.com include:spf.protection.outlook.com ip4:158.194.0.0/16 ip6:2001:718:1401::/48 include:spf.smartemailing.cz include:spf.olc.cz ~all"
www.upol.cz · A
2026-09-05 — Answer records observed
- tonus4-f5.upol.cz · A
158.194.230.160 - tonus4-f5.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=d11ba28a1549c577f6ea743ea05d32335498403dc2fbc01e376288fc0e5dbcafc2beafcb390af07700dd62cb3da858a982d557636e72a8e06ad953d28bcece66; signature_expiration=1790836142; signature_inception=1788241624; signer_name=upol.cz; type_covered=A - www.upol.cz · CNAME
tonus4-f5.upol.cz - www.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz; type_covered=CNAME
www.upol.cz · AAAA
2026-09-05 — Answer records observed
- www.upol.cz · CNAME
tonus4-f5.upol.cz - www.upol.cz · RRSIG
algorithm=13; key_tag=7056; labels=3; original_ttl=86400; signature=cce8862d705186d8ad7ee1108ed3538bd0dd8ea8a2ae29c46d4efc8b5c4f551add80ce0acba8e36653d022df866139eb5bdb85aaf9f4500a8cbbeb4cc19fba6f; signature_expiration=1791020287; signature_inception=1788426664; signer_name=upol.cz; type_covered=CNAME
Changes to upol.cz
No entry for this domain appears in the current public change feed. The feed is a selected sample, so this does not establish that its DNS stayed unchanged.
Start monitoring to build a history from your first check, or explore observed changes across the dataset.
SPF diagnostics
Static observations from the published SPF record. No nested include or redirect dependencies were evaluated. The actual sending IP and evaluation path are needed to assess the RFC 7208 limit of 10 DNS-dependent terms.
Modern mail security across the dataset
The required DNS labels are not queried. Adoption is unknown for this domain and for the population. Apex TXT anomalies are listed separately in the security posture report.
Reverse DNS of inbound MX hosts
These are separately dated observations of inbound MX addresses. They do not identify the actual sending IP. To assess outbound mail, check current forward and reverse DNS of the actual sending IP; FCrDNS and delivery were not measured here.
ax.virusfree.cz
PTR records were observed for all returned addresses of this MX.
DNS attempt: 2026-09-07 05:32:02 UTC. 2 of 2 addresses queried; 2 definite address results in the saved observation.
| Observed IP | Observed PTR names | DNS observation |
|---|---|---|
2001:67c:15a1::a1 | ax.virusfree.cz | PTR observed |
31.7.241.24 | ax.virusfree.cz | PTR observed |
Observed PTR names are outside this domain. Name relationships are not a forward-confirmed reverse DNS test.
bx.virusfree.cz
PTR records were observed for all returned addresses of this MX.
DNS attempt: 2026-09-07 05:32:02 UTC. 2 of 2 addresses queried; 2 definite address results in the saved observation.
| Observed IP | Observed PTR names | DNS observation |
|---|---|---|
2001:67c:15a2::b1 | bx.virusfree.cz | PTR observed |
89.187.156.46 | bq.virusfree.cz | PTR observed |
Observed PTR names are outside this domain. Name relationships are not a forward-confirmed reverse DNS test.
cx.spamfree.cz
PTR records were observed for all returned addresses of this MX.
DNS attempt: 2026-09-07 05:32:02 UTC. 2 of 2 addresses queried; 2 definite address results in the saved observation.
| Observed IP | Observed PTR names | DNS observation |
|---|---|---|
195.24.76.170 | dq.spamfree.cz | PTR observed |
2001:67c:15a3::d1 | dx.spamfree.cz | PTR observed |
Observed PTR names are outside this domain. Name relationships are not a forward-confirmed reverse DNS test.
The observed IP 195.24.76.170 is also associated with 1 other MX hostnames. Outbound use and reputation were not measured.
dx.spamfree.cz
PTR records were observed for all returned addresses of this MX.
DNS attempt: 2026-09-07 05:32:02 UTC. 2 of 2 addresses queried; 2 definite address results in the saved observation.
| Observed IP | Observed PTR names | DNS observation |
|---|---|---|
195.24.76.170 | dq.spamfree.cz | PTR observed |
2001:67c:15a3::d1 | dx.spamfree.cz | PTR observed |
Observed PTR names are outside this domain. Name relationships are not a forward-confirmed reverse DNS test.
The observed IP 195.24.76.170 is also associated with 1 other MX hostnames. Outbound use and reputation were not measured.
Where upol.cz stands
The same snapshot cut by zone, by list position and by how alive the published policies are.
- At this list position the top three mailbox providers hold 60.1% of domains (Google Workspace, Microsoft 365, Unknown / Other).
- Across the dataset 25.1% of DMARC records are inert — policy does nothing and no reports are collected.
Context of .cz
Most used sending platforms among 1,451 SPF-publishing domains in Czechia: Mailchimp 20.1% · Mailgun 10.1% · Amazon SES 9.0% · Mandrill 7.1%. upol.cz runs a stack that is not among the most common in this zone.
How to interpret these observations
MX identifies the observed inbound mailbox or gateway. SPF includes identify services authorised to send for the domain. DMARC shows the published authentication policy. The dataset currently contains 3 populated signal groups for this page.
Observed deliverability context: based on the available observations, this page describes DNS configuration only. It does not represent a complete audit of upol.cz and does not prove that a particular message reaches the inbox or spam folder.
Frequently asked questions
What email provider does upol.cz use?
upol.cz uses Unknown / Other for inbound mail (detected from its primary MX record) as of September 7, 2026, per Live Direct Marketing's daily Tranco top-1M scan.
What ESP does upol.cz use?
upol.cz authorises SmartEmailing in its SPF record as of September 7, 2026.
Does upol.cz enforce DMARC?
No — upol.cz publishes p=none, which only monitors and does not block spoofing (as of September 7, 2026).
Related domain statistics
Nearby domains in the Tranco ranking: betpawa.bj · unhabitat.org · mopera.net · callescort.org
Browse provider data · Compare historical periods · Run an inbox placement test
Data: Email infrastructure of the Tranco top-1M, daily snapshot 2026-09-07, derived from OpenINTEL forward-DNS measurements. Cite with the date — records change daily.