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Questions tagged [ttl]

Time To Live is a mechanism to prevent messages from traversing the network indefinitely

Every IP packet has a Time To Live, it is a counter that gets deducted when it passes a router. It prevents a packet from traversing the network endlessly. If the packets TTL reaches 0 it gets discarded. TTL can be a timestamp or a counter.

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TTL and Google DNS

I've found a similar post about this, however my user can't comment. I wonder why doing dig @8.8.8.8 domain.com prints out different "countdowns" when running it several times in few seconds, as if that domain was cached in different places inside…
whitenoisedb
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Bouncing email due to bad initial MX TTL?

Last Friday night we changed mail servers. We moved off Office 365 to another hosted Exchange Solution (Intermedia.net). We use Godaddy for DNS, and after the server migration stuff was ready and clients were good to go, I edited our MX records. …
Joshua Marshall
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What DNS piece of information do I need to change if I'm going to be moving servers soon?

I'm going to be moving servers for our website soon. Instead of having a long period of 'downtime' for clients because their DNS client is caching the entries for a 'long time', can I hint to the DNS servers that it should check for the IP address…
Pure.Krome
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TTL and traceroute showing different values for same domain

Why am I getting two different outputs for tracert and ping? Ping Result showing total hops of 20 and tracert showing 8. Default ttl value on my Linux machine 64, icmp echo reply ttl value 44. 64-44=20 but tracert is showing only 8 hops. What can…
Cray XT3
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Squid 3.1: external_acl_type ttl won't work

I have custom script for handling Squid3's external_acl_type and it works fine. In this script (btw, its PHP) I turned on logging every request into the file. As far as I know from docs TTL value must provide caching positive answer from my script…
Serhii Matrunchyk
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traceroute command details

As I see in wikipedia, traceroute utility sends a sequence of packets using ICMP protocol in groups of three and with incrementing TTL value to identify the network routers. It also says that Internet Protocol doesn`t guarantee that all the packets…
Saba Jamalian
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Could cached DNS records could potentially double TTL values?

An authoritative DNS server sends an A record with a TTL of 600 seconds. This record is cached by another DNS which in turn replies to a request 599 seconds later for the A record with a 600 second TTL. Since the client that received the record…
nutcase
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NGINX is not respecting DNS TTL of Upstream Server

I have an NGINX TCP load balancer with the following configuration: user myusername; worker_processes auto; error_log /var/log/nginx/error.log; pid /run/nginx.pid; include /usr/share/nginx/modules/*.conf; load_module…
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Is it necessary to set a different ttl before change a Route53 DNS record value?

The first time create the Route53 DNS record with a load balancer origin DNS name with ttl 1 day. After some days, we want to change the value to another load balancer origin DNS name. Do we need to set the target DNS record's ttl to a short time…
freetimetime
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Squid negative_ttl not working

Setup $ squid -v Squid Cache: Version 3.5.20 Service Name: squid configure options: '--build=x86_64-koji-linux-gnu' '--host=x86_64-koji-linux-gnu' '--program-prefix=' '--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' '--sbindir=/usr/sbin'…
Paul Draper
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TTL Changes During Continuous Ping

We use Viasat and have the modem plugged directly into a linux based load balancer. I SSH'ed into the loadbalancer using putty and pinged google When I pinged google this is the result: - PING 8.8.8.8 (8.8.8.8) from x.x.x.x : 64(92) bytes of…
Ixanthylus
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How long does it take to update TTL (Time To Live) of a domain

Say my domain example.com has TTL set to 86400. If i change this through the registrars' panel to 60 when will this change take place? Will it need 86400 seconds ? or will it be instant? I cant find anything online regarding this.
Lithium
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Creating TTL index on number data type

I am trying to create TTL index to delete documents older than 30 min on "generated" field for below sample document sample document: {"_id" : ObjectId("5850308c077b3d1ccc11cef0"), "generated" : NumberLong("1481650316760")} Question 1)is it…
sudheer reddy
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What happens when multiple MX records in a DNS name have different TTLs?

I am wondering what happens when a domain name in DNS has multiple MX records with different Times to Live (TTLs)? For example, what if these are the MX records for example.com? TTL = 3 days,         priority = 1, result = mx1-slow.example.com TTL…
user553702
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Bind caching nameserver MX lookup error for Low TTL Records

We are running Bind (9.8) as Caching Nameserver on a CentOS 6.x based mail server. We get frequent domain not found error for certain domains resulting in mail delivery failure. It was discovered that all those domains have low TTL values…
catman
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