Tomcat download speed

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r_hartman
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Joined: 2009/03/23 15:08:11
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Re: Tomcat download speed

Post by r_hartman » 2011/11/04 07:31:46

mabg wrote:
[code]== BEGIN ifconfig -a ==

<snip 'lo' info>

venet0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:127.0.0.1 P-t-P:127.0.0.1 Bcast:0.0.0.0 Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1
RX packets:18741120 errors:0 dropped:0 overruns:0 frame:0
TX packets:32984569 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1807073000 (1.6 GiB) TX bytes:44781398817 (41.7 GiB)

venet0:0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:188.xx.xx.xx P-t-P:188.xx.xx.xx Bcast:188.xx.xx.xx Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1

== END ifconfig -a ==

== BEGIN route -n ==
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
191.xx.xx.0 0.0.0.0 255.255.255.0 U 0 0 0 venet0
169.xx.xx.0 0.0.0.0 255.255.0.0 U 0 0 0 venet0
0.0.0.0 191.xx.xx.1 0.0.0.0 UG 0 0 0 venet0
== END route -n ==

== BEGIN cat /etc/resolv.conf ==
nameserver 188.xx.xx.xx
== END cat /etc/resolv.conf ==[/code]
While I'm not a full blown network specialist I like to think I know a fair bit about networking, and to me this is puzzling.
From the routing table I would conclude that venet0 is in the 191.xx.xx.0 network, yet ifconfig shows no 191.xx.xx.0 address for venet0, but some local 127.0.0.1 address for a P-t-P connection.
The nameserver is in the 188.xx.xx.xx network, where virtual interface venet0:0 also resides. But that network is missing altogether from the routing table.
I would have expected a line similar to
[code]188.xx.xx.0 0.0.0.0 255.255.255.0 U 0 0 0 venet0:0[/code]
in that routing table, as name resolution now apparently has to be done through the 191.xx.xx.0 network instead of over the 188.xx.xx.xx one.
This might be responsible for slow DNS resolution and, hence, the slow network responses.
However, I would not really associate slow DNS with slow downloads, as once the connection is established DNS should not really matter to the link speed.

Otoh, my network knowledge may be lacking. I sure don't grasp the venet0 info, but that could be because of the point-to-point setup, which I associate with dial-up links.
Then again, venet0:0 is P-t-P also, and does have the expected address, so I really think that venet0 should have a 191.xx.xx.xx address, not 127.0.0.1.

You may want to talk to your provider again about this.

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