私のAレコードが消えました。それは何ですか?

私のAレコードが消えました。それは何ですか?

動的dhcpを使用するように構成された小さなサーバーがあります(dhcpはdnsのホスト名を自動的に更新します)。うまくいきますが、Aレコードの1つが魔法のように消え、PTRレコードは大丈夫です。これが私の設定です。

dhcpd 構成ファイル

authoritative;
ddns-update-style interim;
ddns-updates on;
ddns-ttl 600;
update-static-leases on;
ddns-domainname "mydomain.example";
ddns-rev-domainname "in-addr.arpa";
ignore client-updates;
update-conflict-detection off;
include "/etc/dhcp/dhcp.mydomain.example";
ddns-hostname = pick-first-value(ddns-hostname, option host-name, binary-to-ascii(10,8, "-", leased-address));
max-lease-time 86400;
default-lease-time 14400;
option domain-name-servers 192.168.0.4, 192.168.0.1;
option domain-search-order code 119 = string;
option domain-search-order "mydomain.example fritz.box";
subnet 192.168.0.0 netmask 255.255.255.0 {
        option broadcast-address 192.168.0.255;
        option subnet-mask 255.255.255.0;
        option routers 192.168.0.1;
    option domain-search "mydomain.example";
class "ignored" {
        match if substring(hardware,1,6) = ###################;
}
pool {
        deny members of "ignored";
        range 192.168.0.20 192.168.0.252;
        }
    }
 #
 # 
 # The subnet where the server is attached
     
host samba4 {
hardware ethernet #####################;
fixed-address 192.168.0.5;
ddns-hostname "samba4";
ddns-ttl 604800;
}
zone mydomain.example.
{
primary 192.168.0.4;
key dhcp.mydomain.example;
}
zone 0.168.192.in-addr.arpa.
{
primary 192.168.0.4;
key dhcp.mydomain.example;
}

これは名前が.confです。

options {
    listen-on port 53 { 127.0.0.1; 192.168.0.4; };
    listen-on-v6 port 53 { ::1; };
    querylog yes;
    directory   "/var/named";
    dump-file   "/var/named/data/cache_dump.db";
    statistics-file "/var/named/data/named_stats.txt";
    memstatistics-file "/var/named/data/named_mem_stats.txt";
    recursing-file  "/var/named/data/named.recursing";
    secroots-file   "/var/named/data/named.secroots";
    allow-query     { localhost; 192.168.0.0/24; 10.2.0.0/24;};
    /* 
     - If you are building an AUTHORITATIVE DNS server, do NOT enable recursion.
     - If you are building a RECURSIVE (caching) DNS server, you need to enable 
       recursion. 
     - If your recursive DNS server has a public IP address, you MUST enable access 
       control to limit queries to your legitimate users. Failing to do so will
       cause your server to become part of large scale DNS amplification 
       attacks. Implementing BCP38 within your network would greatly
       reduce such attack surface 
    */
    recursion yes;
    dnssec-enable yes;
    dnssec-validation yes;
    /* Path to ISC DLV key */
    bindkeys-file "/etc/named.iscdlv.key";
    managed-keys-directory "/var/named/dynamic";
    pid-file "/run/named/named.pid";
    session-keyfile "/run/named/session.key";
        allow-new-zones yes;
        dnssec-must-be-secure "mydomain.example" yes;
        dnssec-must-be-secure "0.168.192.in-addr.arpa" yes;
        allow-transfer {127.0.0.1; };
        allow-recursion {127.0.0.1; 192.168.0.0/24; 10.2.0.24; };
        version "Proot";
        tkey-gssapi-keytab "/etc/dns.keytab";
        tkey-domain "MYDOMAIN.EXAMPLE";
};
server 10.3.0.2 {
    keys {  my-tsig; };
};
key dhcp.mydomain.example {
    algorithm hmac-sha512;
    secret "################";
};
key "my-tsig" {
algorithm HMAC-SHA512;
    secret "################";
};
key "my-tsig2" {
algorithm HMAC-SHA512;
    secret "################";
};
controls {
        inet 192.168.0.4 port 953 allow { 192.168.0.4; 127.0.0.1; } keys { dhcp.mydomain.example; };
        inet 127.0.0.1 port 953 allow { 127.0.0.1;  } keys { dhcp.mydomain.example; };
        };
zone "." IN {
    type hint;
    file "named.ca";
};
zone "mydomain.example." IN {
    type master;
    file "/var/named/data/mydomain.example.zone";
        allow-transfer {key my-tsig2; };
    update-policy {
    grant dhcp.mydomain.example. wildcard * A TXT SRV CNAME MX DHCID;
        grant [email protected] wildcard * A AAAA TXT SRV CNAME MX;
        grant [email protected] wildcard * A AAAA TXT SRV CNAME MX;
        grant [email protected] wildcard * A TXT SRV CNAME MX;
 };
        key-directory "/var/named/data";
        auto-dnssec maintain;
        inline-signing yes;
    /*
     * the list of principals and what they can change is created
     * dynamically by Samba, based on the membership of the domain controllers
     * group. The provision just creates this file as an empty file.
     */
    #include "/var/lib/samba/private/named.conf.update";
    /* we need to use check-names ignore so _msdcs A records can be created */
    check-names ignore;
};
zone "0.168.192.in-addr.arpa" {
    type master;
    file "/var/named/data/0.168.192.in-addr.arpa";
        allow-transfer {key my-tsig2; };
    update-policy {
    grant dhcp.mydomain.example. wildcard * PTR;
        grant [email protected] wildcard * PTR;
        grant [email protected] wildcard * PTR;
        grant [email protected] wildcard * PTR;
    };
        auto-dnssec maintain;
        key-directory "/var/named/data";
        inline-signing yes;
};
zone "otherzone.priv." IN {
        type slave;
        masters {10.3.0.2; };
        file "/var/named/data/otherzone.priv.zone";
        key-directory "/var/named/data";
        auto-dnssec maintain;
        inline-signing yes;
        /*
         * the list of principals and what they can change is created
         * dynamically by Samba, based on the membership of the domain controllers
         * group. The provision just creates this file as an empty file.
         */
        #include "/var/lib/samba/private/named.conf.update";
        /* we need to use check-names ignore so _msdcs A records can be created */
        check-names ignore;
};
zone "0.3.10.in-addr.arpa" {
    type slave;
    file "/var/named/data/0.3.10.in-addr.arpa.zone";
        masters {10.3.0.2; };
        auto-dnssec maintain;
        key-directory "/var/named/data";
        inline-signing yes;
};
include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";

ログに奇妙なことはありません。名前付きデータディレクトリに移動すると、私の欠落レコードが存在するようですが、掘り下げるとそうではありません。

grep -irl disappeared.mydomain.example *
0.168.192.in-addr.arpa
0.168.192.in-addr.arpa.signed
mydomain.example.zone.jnl
mydomain.example.zone.signed
mydomain.example.zone.signed.jnl

発掘が消えました。mydomain.example

; <<>> DiG 9.11.26-RedHat-9.11.26-4.el8_4 <<>> disappeared.mydomain.example
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 192
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; COOKIE: 172e90668acc5f522b6add4b617edbeb3909928cefd32999 (good)
;; QUESTION SECTION:
;disappeared.mydomain.example.      IN  A

;; AUTHORITY SECTION:
mydomain.example.       86400   IN  SOA dns1.mydomain.example. root.mydomain.example. 2020140075 60 120 604800 86400

;; Query time: 0 msec
;; SERVER: 192.168.0.4#53(192.168.0.4)
;; WHEN: Sun Oct 31 19:09:47 CET 2021
;; MSG SIZE  rcvd: 123

dig -x 192.168.0.32が正しい名前を返すようにします。それは何ですか? dhcpd.leases ファイルからリースを手動で削除してから、クライアントから Network Manager を再起動し、正しい A レコードを再挿入することを確認できます。

ベストアンサー1

この解決策はうまくいくようです。

ddns-ttl 600;
default-lease-time 14400;

少し違う

両方とも同じ値を試してみました。

ddns-ttl 600;
default-lease-time 600;

動作しますが、リースファイルを再作成する必要があります。

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