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  • Calculate the size of a DNS record in the cache

    From Mik J@mikydevel@yahoo.fr to bind-users on Tue Jul 28 22:47:46 2020
    From Newsgroup: comp.protocols.dns.bind

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    Hello,
    My cache is 100MB and I'd like to know how many records can fit inside.I suppose that it depends on the record: isc.org is 7 characters and shorter than http://www.example.com
    And it probably depends on the type and adress.
    So which size would isc.org A 1.1.1.1 be ?

    I ask my question because I was wondering how many nxdomainattack000000001.example.com, nxdomainattack000000002.example.com...can I generate before fil in the cache of my recursive server
    According to the RFC, if my example.com SOA TTL is 86400, the NXDOMAIN entry would remain in the cache for 1 day.
    Thank you for sharing your thoughts



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    <html><head></head><body><div class=3D"ydpe277e8byahoo-style-wrap" style=3D= "font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;">= <div dir=3D"ltr" data-setdir=3D"false">Hello,</div><div dir=3D"ltr" data-se= tdir=3D"false"><br></div><div dir=3D"ltr" data-setdir=3D"false">My cache is=
    100MB and I'd like to know how many records can fit inside.</div><div dir= =3D"ltr" data-setdir=3D"false">I suppose that it depends on the record: isc= .org is 7 characters and shorter than <a href=3D"http://www.example.com" re= l=3D"nofollow" target=3D"_blank">http://www.example.com</a></div><div><br><= /div><div>And it probably depends on the type and adress.</div><div><br></d= iv><div dir=3D"ltr" data-setdir=3D"false">So which size would isc.org A 1.1= .1.1 be ?<br></div><div><br></div><div dir=3D"ltr" data-setdir=3D"false">I = ask my question because I was wondering how many nxdomainattack000000001.ex= ample.com, <span>nxdomainattack000000002.example.com...can I generate befor=
    e fil in the cache of my recursive server</span></div><div dir=3D"ltr" data= -setdir=3D"false"><span><br></span></div><div dir=3D"ltr" data-setdir=3D"fa= lse"><span>According to the RFC, if my example.com SOA TTL is 86400, the NX= DOMAIN entry would remain in the cache for 1 day.</span></div><div dir=3D"l= tr" data-setdir=3D"false"><span><br></span></div><div dir=3D"ltr" data-setd= ir=3D"false"><span>Thank you for sharing your thoughts</span><br></div><div= ><br></div><div dir=3D"ltr" data-setdir=3D"false"><br></div></div></body></= html>
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