`jestedliberec.cz`

DNSSEC	⚠️ Not signed
A	2a01:28:ca:72::100:195^{🇨🇿 SuperNetwork2a01:28::/32 s.r.o.}
		PTR	`lba.as4u.org`
A	88.86.100.195^{🇨🇿 SuperNetwork88.86.96.0/19 s.r.o.}
NS	`ns.as4u.org` ⭐
		A	2a01:28:ca:72::100:200^{🇨🇿 SuperNetwork2a01:28::/32 s.r.o.}
			PTR	`ns-01.as4u.org`
			PTR	`ns.as4u.org`
		A	88.86.100.200^{🇨🇿 SuperNetwork88.86.96.0/19 s.r.o.}
NS	`ns.as4u.cz`
		A	2a01:28:ca:72::100:250^{🇨🇿 SuperNetwork2a01:28::/32 s.r.o.}
			PTR	`ns.as4u.cz`
			PTR	`ns-02.as4u.org`
		A	88.86.100.250^{🇨🇿 SuperNetwork88.86.96.0/19 s.r.o.}
NS	`ns.district9.cz`
		A	2a03:3b40:fe:68f::1^{🇨🇿 MASTER-AS2a03:3b40::/40 VPSFREE-IPV6-PRG2}
			PTR	`ns.district9.cz`
		A	37.205.8.46^{🇨🇿 MASTER-AS37.205.8.0/22 RELBIT-VPSFREE}
			PTR	`ns.district9.cz`
MX	`mx-01.jestedliberec.cz` ⭐
		A	2a01:28:ca:72::100:231^{🇨🇿 SuperNetwork2a01:28::/32 s.r.o.}
			PTR	`mx-01.as4u.org`
		A	88.86.100.231^{🇨🇿 SuperNetwork88.86.96.0/19 s.r.o.}
MX	`mx-02.jestedliberec.cz`⁽¹⁰⁾
		A	2a01:28:ca:72::100:233^{🇨🇿 SuperNetwork2a01:28::/32 s.r.o.}
			PTR	`mx-02.as4u.org`
		A	88.86.100.233^{🇨🇿 SuperNetwork88.86.96.0/19 s.r.o.}
SOA	`ns.as4u.org`hostmaster@as4u.org 2018-08-24 #0

`cz`

	DNSSEC	🔒 Signed (DS record present)
	NS	`a.ns.nic.cz` ⭐
	NS	`b.ns.nic.cz`
	NS	`c.ns.nic.cz`
	NS	`d.ns.nic.cz`
	SOA	`a.ns.nic.cz`hostmaster@nic.cz serial=1777069038

Subdomains

mx-01.jestedliberec.cz

mx-02.jestedliberec.cz

Same first word

jestedliberec.cz

DNS History

7 records (7 active, 0 former)

●NSns.as4u.cz2018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

●NSns.as4u.org2018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

●NSns.district9.cz2018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

●MXmx-01.jestedliberec.cz2018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

●MXmx-02.jestedliberec.cz2018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

●A2a01:28:ca:72::100:1952018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

●A88.86.100.1952018-06-11 → 2026-04-24 · 2 obs

● 2018-06-11 15:27:10
● 2026-04-24 23:12:30

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
cz	a.ns.nic.cz, b.ns.nic.cz, c.ns.nic.cz, d.ns.nic.cz	-
jestedliberec.cz	ns.as4u.cz, ns.as4u.org, ns.district9.cz	2 records

✅ Authoritative Response

Server:88.86.100.250

NS records: ns.as4u.cz, ns.as4u.org, ns.district9.cz

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for jestedliberec.cz (unsigned zone)

⏱️ Timing

Total: 1093ms | Queries: -

📄 Records

Type	Count	Sample Data
A	1	`88.86.100.195`
AAAA	1	`2a01:28:ca:72::100:195`
NS	3	`ns.district9.cz, ns.as4u.cz...`
MX	2	`mx-01.jestedliberec.cz (pri: 5), mx-02.jestedliberec.cz (pri: 10)`
SOA	1	`ns.as4u.org hostmaster.as4u.org`

📌 Glue Records Collected

Total: 2

Out-of-bailiwick: 2 (ns.as4u.cz, ns.as4u.cz)

Analysis

Hierarchy

jestedliberec.cz is a parent of mx-01.jestedliberec.cz and mx-02.jestedliberec.cz.

IP Addresses

jestedliberec.cz points to two IP numbers: 2a01:28:ca:72::100:195 and 88.86.100.195.

Other host names, for instance www.kultura-kadan.cz, pvskoly.cz, kralovehradeckyregion.cz, zsschsady.cz and mesto-rokytnice.cz share IP numbers with jestedliberec.cz.

Name Servers

The delegation for jestedliberec.cz is handled by three name servers: ns.as4u.cz, ns.district9.cz and ns.as4u.org.

jestedliberec.cz at least partially shares name servers with other domains, for instance mesto-frydlant.cz, zsschsady.cz, obecjinacovice.cz, stredni-cechy.eu and profi4u.cz.

These name servers are commonly used with the name servers ns.forpsi.net.

Two IP numbers per host:

ns.as4u.cz points to 2a01:28:ca:72::100:250 and 88.86.100.250.

ns.district9.cz points to 2a03:3b40:fe:68f::1 and 37.205.8.46.

ns.as4u.org points to 2a01:28:ca:72::100:200 and 88.86.100.200.

Mail Servers

jestedliberec.cz is handled by two mail servers: mx-01.jestedliberec.cz and mx-02.jestedliberec.cz.

Host names with two IP numbers: mx-01.jestedliberec.cz points to 2a01:28:ca:72::100:231 and 88.86.100.231; mx-02.jestedliberec.cz points to 2a01:28:ca:72::100:233 and 88.86.100.233.

jestedliberec.cz - robtex.com