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

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Cisco 3560+ipservices — IGMP snooping issue with TTL=1

I've got a C3560 with Enhanced (IPSERVICES) image, routing multicast between its VLANs with no external multicast router. It's serving a test environment where developers may generate multicast ...
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Any disadvantage to short DNS TTL? [closed]

Any disadvantage to short DNS TTL?
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Differences of the TTL value in Tracert and Ping

When I ping localhost on my Windows XP system, the TTL value returned is 128 and it shows me that the default TTL value in the ping for my system is 128. Then when I ping google.com the returned TTL ...
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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 ...
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Using a low TTL to help prevent extended periods of downtime

Is it feasible to set my domain's TTL to a very low value (a couple of minutes) so that, if my main host goes down for an extended period of time, I can update the DNS records in my main host to point ...
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How can I see Time-To-Live (TTL) for a DNS record?

I would like to see the Time-To-Live (TTL) value for a CNAME record. I have access to dig (on Apple Mac OS X), which gives me an answer like this: % dig host.example.gov <*SNIP*> ;; ANSWER ...
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DNS TTL problem

So I have an external network card and an internal NIC on my windows 2008 R2 server. When I try to connect to some websites, i get a timeout which is a TTL problem. It goes away when i disable the ...
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hightraffic dns ttl record

Whats bestpratice TTL for hightraffic www sites? Should there be a high TTL to make dnsservers around cache longer so the dnsserver wont have to get requests to often?
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ICMP - TTL - Trace Route

I asked this question at Stack Overflow and then thought this may be the better place to ask. Given the following situation: PC --- |aa RTR1 bb| --- |aa RTR2 bb| --- |aa RTR3 bb| etc Each of the ...
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CNAME and A record have different TTLs. Which one will be cached?

If a CNAME has a TTL of 1 hour that points to an A record with a TTL of 1 minute, will someone who looks up this CNAME have the entire result cached for 1 hour, or will it will keep having to lookup ...
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Small TTL values

What is a TTL in DNS? What is the advantage of having small TTL?
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DDNS + DHCPD : Once lease runs out, does DNS entry get removed?

Once there are several hundred adhoc machines being brought up, each with a unique name. Their hostname gets added to the DNS. Then upon TTL expiring, will the DNS entry still be reachable, or if the ...
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What percentage of nameservers honor TTL these days?

Some years ago I had to do several DNS changes over the course of several weeks as I moved bits of equipment from one data center to the other. At the time that I did this, about 95% of the ...
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Recommended DNS SOA record TTL default?

We currently have our DNS SOA record set to the following for stackoverflow.com: primary name server = ns1.p19.dynect.net serial = 2009090909 refresh = 3600 (1 hour) retry = 600 ...
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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 ...
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2answers
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Recommend a content delivery network (CDN) for a specific purpose [closed]

could you please recommend a CDN for the following use: 1) Ability to update files on the edge servers automatically through API, so it should take no more than 5-10 minutes to make a new version of ...
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What does “TTL expired in transit” mean on a ping attempt?

We get the message “TTL expired in transit” when we try to ping to a server in a different network segment. When we run tracert, 4 ip addresses repeat themselves indefinitely: 14 60 ms 59 ms ...
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Recommended DNS TTL

I know it could be very different based on the situation, but for hosting a website with no plans to move the hosting server what is a good TTL to set on the DNS record?