LinuxQuestions.org - Ping & Server Speed

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Ping & Server Speed

What parameter shows the connectio of the server?

I'm looking for a paramter that shows server speed capability.

E.g:
[mike@MS mike]$ ping linuxquestions.com
PING linuxquestions.com (213.130.63.234) 56(84) bytes of data.
64 bytes from usl0000001-vip3.eu.verio.net (213.130.63.234): icmp_seq=1 ttl=48 time=91.5 ms
64 bytes from usl0000001-vip3.eu.verio.net (213.130.63.234): icmp_seq=2 ttl=48 time=88.4 ms

The time parameter(time=91.5 ms) shows how long it took for your request to complete. Obviously the smaller the number the faster the server speed.

Thanks for the good answer.

One more question: TTL has any effect on server speed ?
What the purpose of TTL in the output ?

Thanks

I believe that stands for Time To Live. This is what the ping man page says:

The TTL value of an IP packet represents the maximum number of IP routers that the packet can go through before being thrown away. In current practice you can expect each router in the Internet to decre-ment the TTL field by exactly one.

Why the TTL number is not constant ?

Last question, why some servers is not possible to ping..

[mike@MS mike]$ ping nyt.com
PING nyt.com (199.239.137.217) 56(84) bytes of data.
From 128.241.244.54 icmp_seq=2 Packet filtered

They could have there firewall configured to drop the icmp ping packets or the server could simply be down.

and TTL isn't constant but decremented at each hop to prevent packets that that are unable to reach their destination bouncing around the internet going nowhere until the end of time - or someone pulls the plug.

Quote:

Originally posted by Looking_Lost
and TTL isn't constant but decremented at each hop to prevent packets that that are unable to reach their destination bouncing around the internet going nowhere until the end of time - or someone pulls the plug.

Ok .. But When I ping two different servers, I got differemt TTL number..

E.g:

[mike@MS .galeon]$ ping rackspace.com
PING rackspace.com (64.39.2.185) 56(84) bytes of data.
64 bytes from cirrus.rackspace.com (64.39.2.185): icmp_seq=1 ttl=113 time=60.8 ms

&

[mike@MS .galeon]$ ping rackshake.net
PING rackshake.net (213.58.153.4) 56(84) bytes of data.
64 bytes from hosting1.sonet.pt (213.58.153.4): icmp_seq=1 ttl=40 time=162 ms

TTL for rackspace.com is 113
TTL for for rackshack.net is 40 ...

Why they are different.. Same protocol right ??

Quote:

TTL details

The TTL value of an IP packet represents the maximum number of IP routers that the packet can go through before being thrown away. In current practice you can expect each router in the Internet to decrement the TTL field by exactly one. The TCP/IP specification states that the TTL field for TCP packets should be set to 60, but many systems use smaller values (4.3 BSD uses 30, 4.2 uses 15).

The maximum possible value of this field is 255, and most UNIX systems (including QNX) set the TTL field of ICMP ECHO_REQUEST packets to 255. Thus you'll find you can "ping" some hosts, but not reach them with telnet or ftp.

In normal operation, ping prints the ttl value from the packet it receives. When a remote system receives a ping packet, it can do one of three things with the TTL field in its response:

* Not change it -- this is what Berkeley UNIX systems did before the 4.3BSD-Tahoe release. The TTL value in the received packet is 255 minus the number of routers in the roundtrip path.
* Set it to 255 -- this is what current Berkeley UNIX systems do. The TTL value in the received packet is 255 minus the number of routers in the path from the remote system to the pinging host.
* Set it to some other value -- some machines use the same value for ICMP packets that they use for TCP packets; for example, either 30 or 60. Others may use completely wild values.

Never thought of that myself before so I did a quick search and turned up the above. Ya learn something new everyday

:)