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Old 08-25-2008, 12:41 PM   #1
energiza
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Registered: Oct 2004
Location: Queretaro Mexico
Distribution: SUSE 10.2
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TCP sincronization some packets lost


Hello Again:

I have a network with 2 linux servers and 2 windows servers. One linux server (name quadcore) is the one handling telnet, ftp, http, mysql services via the router to the internet. Within the lan it provides the same services as well. The second linux machine (name inflinux) is a backup server just in case to replace the main linux server (it also gives the same services, telnet, ftp, http but only to the LAN). Inflinux is making backup copies of the mysql databases. Every 4 hours it does a mysqldump from quadcore. Then I noticed that certain mysqldump were failing; not connecting.

I'm located outside the router, and I access that network via telnet and ftp, etc. So I entered quadcore (main server) and from there I telnet'ed to inflinux (backup server). Finally I ping'ed from inflinux (192.168.76.15) to quadcore (192.168.76.6).

Then I exit inflinux and ping'ed from quadcore to inflinux.

Notice the packet loss is the same (60% in this case. I've go 52% in other times). HTTP transmission is ok, mysqldump when successful it gets the data without missing bits. But the fact is that there are problems in communication that cause delays.

Do you think it's some problem in sincronization?. One txqueuelen is 100 (quadcore) while inflinux is 1000.

I also get to have delays when trying to telnet main server quadcore, but in general this is rare. I did a tcpdump and I don't see more references but to local machines.

Firewall in quadcore is off. Firewall in inflinux has all services allowed (http, ftp, mysql, samba).

Thanks for the help.!!!

FIRST PING FROM INFLINUX TO QUADCORE

javier@inflinux:~> ping 192.168.76.6
PING 192.168.76.6 (192.168.76.6) 56(84) bytes of data.
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=7 ttl=64 time=0.371 ms
64 bytes from 192.168.76.6: icmp_seq=8 ttl=64 time=0.366 ms
64 bytes from 192.168.76.6: icmp_seq=9 ttl=64 time=0.376 ms
64 bytes from 192.168.76.6: icmp_seq=10 ttl=64 time=0.344 ms
64 bytes from 192.168.76.6: icmp_seq=11 ttl=64 time=0.345 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=17 ttl=64 time=0.349 ms
64 bytes from 192.168.76.6: icmp_seq=18 ttl=64 time=0.370 ms
64 bytes from 192.168.76.6: icmp_seq=19 ttl=64 time=0.365 ms
64 bytes from 192.168.76.6: icmp_seq=20 ttl=64 time=0.373 ms
64 bytes from 192.168.76.6: icmp_seq=21 ttl=64 time=0.340 ms
64 bytes from 192.168.76.6: icmp_seq=22 ttl=64 time=0.344 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=31 ttl=64 time=0.382 ms
64 bytes from 192.168.76.6: icmp_seq=32 ttl=64 time=0.343 ms
64 bytes from 192.168.76.6: icmp_seq=33 ttl=64 time=0.356 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=39 ttl=64 time=0.440 ms
64 bytes from 192.168.76.6: icmp_seq=40 ttl=64 time=0.436 ms
64 bytes from 192.168.76.6: icmp_seq=41 ttl=64 time=0.353 ms
64 bytes from 192.168.76.6: icmp_seq=42 ttl=64 time=0.426 ms
64 bytes from 192.168.76.6: icmp_seq=43 ttl=64 time=0.344 ms
64 bytes from 192.168.76.6: icmp_seq=44 ttl=64 time=0.342 ms
64 bytes from 192.168.76.6: icmp_seq=45 ttl=64 time=0.350 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=53 ttl=64 time=0.373 ms
64 bytes from 192.168.76.6: icmp_seq=54 ttl=64 time=0.383 ms
64 bytes from 192.168.76.6: icmp_seq=55 ttl=64 time=0.342 ms
64 bytes from 192.168.76.6: icmp_seq=56 ttl=64 time=0.346 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=65 ttl=64 time=0.378 ms
64 bytes from 192.168.76.6: icmp_seq=66 ttl=64 time=0.342 ms
64 bytes from 192.168.76.6: icmp_seq=67 ttl=64 time=0.349 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=76 ttl=64 time=0.379 ms
64 bytes from 192.168.76.6: icmp_seq=77 ttl=64 time=0.346 ms
64 bytes from 192.168.76.6: icmp_seq=78 ttl=64 time=0.137 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted
64 bytes from 192.168.76.6: icmp_seq=86 ttl=64 time=0.361 ms
64 bytes from 192.168.76.6: icmp_seq=87 ttl=64 time=0.372 ms
64 bytes from 192.168.76.6: icmp_seq=88 ttl=64 time=0.344 ms
64 bytes from 192.168.76.6: icmp_seq=89 ttl=64 time=0.345 ms
64 bytes from 192.168.76.6: icmp_seq=90 ttl=64 time=0.348 ms
ping: sendmsg: Operation not permitted
ping: sendmsg: Operation not permitted

--- 192.168.76.6 ping statistics ---
92 packets transmitted, 36 received, 60% packet loss, time 91012ms
rtt min/avg/max/mdev = 0.137/0.357/0.440/0.046 ms


SECOND PING FROM QUADCORE TO INFLINUX

NOTICE SKIPPED SEQ NO.

javier@quadcore:~> ping inflinux
PING inflinux (192.168.76.15) 56(84) bytes of data.
64 bytes from inflinux (192.168.76.15): icmp_seq=1 ttl=64 time=3.32 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=6 ttl=64 time=0.251 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=10 ttl=64 time=0.249 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=11 ttl=64 time=0.252 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=12 ttl=64 time=0.248 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=13 ttl=64 time=0.253 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=21 ttl=64 time=0.249 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=22 ttl=64 time=0.249 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=23 ttl=64 time=0.249 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=24 ttl=64 time=0.248 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=33 ttl=64 time=0.252 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=34 ttl=64 time=0.249 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=35 ttl=64 time=0.252 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=44 ttl=64 time=0.251 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=45 ttl=64 time=0.252 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=46 ttl=64 time=0.250 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=49 ttl=64 time=0.230 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=51 ttl=64 time=0.258 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=52 ttl=64 time=0.256 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=53 ttl=64 time=0.253 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=54 ttl=64 time=0.250 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=55 ttl=64 time=0.253 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=56 ttl=64 time=0.250 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=57 ttl=64 time=0.253 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=66 ttl=64 time=0.252 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=67 ttl=64 time=0.249 ms
64 bytes from inflinux (192.168.76.15): icmp_seq=68 ttl=64 time=0.251 ms

--- inflinux ping statistics ---
69 packets transmitted, 27 received, 60% packet loss, time 68007ms
rtt min/avg/max/mdev = 0.230/0.364/3.326/0.581 ms
 
Old 08-25-2008, 12:49 PM   #2
chort
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Registered: Jul 2003
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It's more likely there is a duplex mis-match between one of the network cards and the switch it's plugged into.
 
Old 08-25-2008, 01:41 PM   #3
energiza
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Location: Queretaro Mexico
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This is the ifconfig of quadcore for its eth0:

eth0 Link encap:Ethernet HWaddr 00:1C:C0:35:54:F0
inet addr:192.168.76.6 Bcast:192.168.76.255 Mask:255.255.255.0
inet6 addr: fe80::21c:c0ff:fe35:54f0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:264174 errors:0 dropped:0 overruns:0 frame:0
TX packets:278374 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:27311771 (26.0 Mb) TX bytes:396425389 (378.0 Mb)

and for the other server inflinux:

eth0 Link encap:Ethernet HWaddr 00:15:58:23:ED:17
inet addr:192.168.76.15 Bcast:192.168.76.255 Mask:255.255.255.0
inet6 addr: fe80::215:58ff:fe23:ed17/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3201030 errors:0 dropped:0 overruns:0 frame:0
TX packets:3237135 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:229245144 (218.6 Mb) TX bytes:477458716 (455.3 Mb)
Interrupt:217 Base address:0xe200

This a brief tcpdump to show the delays:

Notice at 22:26:40 I issue a "telnet" to quadcore from inflinux, while I keep tcpdump in the background within inflinux. As you can see there are messages from .local.domain machines possibly DNS servers (windows machines I don't control).

22:26:40.068263 IP 192.168.75.102.netbios-dgm > 192.168.76.255.netbios-dgm: NBT UDP PACKET(138)
22:26:40.068596 IP inflinux.site.solid-mux > servigi.pdm.local.domain: 16255+ PTR? 255.76.168.192.in-addr.arpa. (45)
22:26:40.068838 IP servigi.pdm.local.domain > inflinux.site.solid-mux: 16255 NXDomain* 0/1/0 (132)
22:26:40.069027 IP inflinux.site.solid-mux > servigi.pdm.local.domain: 48599+ PTR? 102.75.168.192.in-addr.arpa. (45)
22:26:40.157613 IP servigi.pdm.local.domain > inflinux.site.solid-mux: 48599 NXDomain* 0/0/0 (45)
22:26:40.284380 IP 192.168.76.6.37569 > inflinux.site.telnet: S 30159679:30159679(0) win 5840 <mss 1460,sackOK,timestamp 31704488 0,nop,wscale 7>
22:26:41.411141 IP servpdm.pdm.local.55871 > 255.255.255.255.11050: UDP, length: 664
22:26:44.511539 IP 192.168.75.6.netbios-dgm > 192.168.76.255.netbios-dgm: NBT UDP PACKET(138)
22:26:44.512164 IP inflinux.site.solid-mux > servigi.pdm.local.domain: 64527+ PTR? 6.75.168.192.in-addr.arpa. (43)
22:26:44.605830 IP servigi.pdm.local.domain > inflinux.site.solid-mux: 64527 NXDomain* 0/0/0 (43)
22:26:46.285356 IP 192.168.76.6.37569 > inflinux.site.telnet: S 30159679:30159679(0) win 5840 <mss 1460,sackOK,timestamp 31705988 0,nop,wscale 7>
22:26:58.287303 IP 192.168.76.6.37569 > inflinux.site.telnet: S 30159679:30159679(0) win 5840 <mss 1460,sackOK,timestamp 31708988 0,nop,wscale 7>
 
Old 08-25-2008, 03:59 PM   #4
chort
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The delay in telnet is 192.168.76.6 is not seeing ACK packets from inflinux. Either inflinux isn't receiving the SYN, or the ACK is being dropped on the way back. It's pretty clear you have a lot of packet loss on your network, the question is why. Try this on both the machines involved:
Code:
$ sudo ethtool eth0
and report the output. Also, what is the output from:
Code:
$ netstat -s
on each machine?
 
Old 08-25-2008, 06:46 PM   #5
energiza
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Location: Queretaro Mexico
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Thanks a lot:

For main machine quadcore:

By the way, I already tried turning off the firewall at backup server inflinux, but the delays continue.

Quote:
quadcore:/home/javier # sudo ethtool eth0


Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: pumbag
Wake-on: g
Current message level: 0x00000001 (1)
Link detected: yes
quadcore:/home/javier # netstat -s

Ip:
1765627 total packets received
54 with invalid addresses
0 forwarded
0 incoming packets discarded
1765573 incoming packets delivered
1827589 requests sent out
Icmp:
267 ICMP messages received
0 input ICMP message failed.
ICMP input histogram:
destination unreachable: 1
echo requests: 37
echo replies: 229
42 ICMP messages sent
0 ICMP messages failed
ICMP output histogram:
destination unreachable: 5
echo replies: 37
Tcp:
36193 active connections openings
37063 passive connection openings
0 failed connection attempts
39 connection resets received
2 connections established
1736099 segments received
1784788 segments send out
41296 segments retransmited
0 bad segments received.
25 resets sent
Udp:
26079 packets received
4 packets to unknown port received.
0 packet receive errors
956 packets sent
TcpExt:
4 invalid SYN cookies received
ArpFilter: 0
37270 TCP sockets finished time wait in fast timer
3565 delayed acks sent
2 delayed acks further delayed because of locked socket
Quick ack mode was activated 96 times
922186 packets directly queued to recvmsg prequeue.
6037657 packets directly received from backlog
440479117 packets directly received from prequeue
197171 packets header predicted
396082 packets header predicted and directly queued to user
TCPPureAcks: 363783
TCPHPAcks: 738582
TCPRenoRecovery: 0
TCPSackRecovery: 38922
TCPSACKReneging: 0
TCPFACKReorder: 0
TCPSACKReorder: 0
TCPRenoReorder: 0
TCPTSReorder: 0
TCPFullUndo: 0
TCPPartialUndo: 0
TCPDSACKUndo: 0
TCPLossUndo: 40
TCPLoss: 37844
TCPLostRetransmit: 0
TCPRenoFailures: 0
TCPSackFailures: 57
TCPLossFailures: 0
TCPFastRetrans: 40061
TCPForwardRetrans: 75
TCPSlowStartRetrans: 25
TCPTimeouts: 253
TCPRenoRecoveryFail: 0
TCPSackRecoveryFail: 737
TCPSchedulerFailed: 0
TCPRcvCollapsed: 0
TCPDSACKOldSent: 94
TCPDSACKOfoSent: 0
TCPDSACKRecv: 6
TCPDSACKOfoRecv: 0
TCPAbortOnSyn: 0
TCPAbortOnData: 13
TCPAbortOnClose: 5
TCPAbortOnMemory: 0
TCPAbortOnTimeout: 2
TCPAbortOnLinger: 0
TCPAbortFailed: 0
TCPMemoryPressures: 0
quadcore:/home/javier #
For Inflinux: ( oops! I've had this server running for almost 2 years and not aware of this!!)

How can I fix this?, what am I missing? Thanks

Quote:
inflinux:/home/javier # sudo ethtool eth0

Settings for eth0:
No data available
inflinux:/home/javier # netstat -s

Ip:
3275117047 total packets received
0 forwarded
0 incoming packets discarded
3275089279 incoming packets delivered
3275158000 requests sent out
2173 outgoing packets dropped
Icmp:
476 ICMP messages received
0 input ICMP message failed.
ICMP input histogram:
echo requests: 314
echo replies: 162
314 ICMP messages sent
0 ICMP messages failed
ICMP output histogram:
echo replies: 314
Tcp:
329202591 active connections openings
329202869 passive connection openings
0 failed connection attempts
328843808 connection resets received
2 connections established
3275065127 segments received
3275203839 segments send out
25159 segments retransmited
0 bad segments received.
642807784 resets sent
Udp:
23679 packets received
0 packets to unknown port received.
0 packet receive errors
1261 packets sent
TcpExt:
314315295 invalid SYN cookies received
8 packets pruned from receive queue because of socket buffer overrun
ArpFilter: 0
87553 TCP sockets finished time wait in fast timer
2436 time wait sockets recycled by time stamp
646124 delayed acks sent
9861504 delayed acks further delayed because of locked socket
Quick ack mode was activated 91 times
3045969 packets directly queued to recvmsg prequeue.
2055648 packets directly received from backlog
22801343 packets directly received from prequeue
3665513 packets header predicted
134965 packets header predicted and directly queued to user
TCPPureAcks: 658821053
TCPHPAcks: 4501590
TCPRenoRecovery: 0
TCPSackRecovery: 0
TCPSACKReneging: 0
TCPFACKReorder: 0
TCPSACKReorder: 0
TCPRenoReorder: 0
TCPTSReorder: 0
TCPFullUndo: 0
TCPPartialUndo: 0
TCPDSACKUndo: 0
TCPLossUndo: 24611
TCPLoss: 0
TCPLostRetransmit: 0
TCPRenoFailures: 0
TCPSackFailures: 0
TCPLossFailures: 0
TCPFastRetrans: 0
TCPForwardRetrans: 0
TCPSlowStartRetrans: 0
TCPTimeouts: 25203
TCPRenoRecoveryFail: 0
TCPSackRecoveryFail: 0
TCPSchedulerFailed: 3
TCPRcvCollapsed: 491
TCPDSACKOldSent: 375
TCPDSACKOfoSent: 21
TCPDSACKRecv: 68
TCPDSACKOfoRecv: 0
TCPAbortOnSyn: 0
TCPAbortOnData: 328464046
TCPAbortOnClose: 344481
TCPAbortOnMemory: 0
TCPAbortOnTimeout: 38
TCPAbortOnLinger: 0
TCPAbortFailed: 0
TCPMemoryPressures: 0
inflinux:/home/javier #

Last edited by energiza; 08-25-2008 at 06:48 PM.
 
Old 08-25-2008, 08:29 PM   #6
energiza
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Registered: Oct 2004
Location: Queretaro Mexico
Distribution: SUSE 10.2
Posts: 51

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chort I forgot to mention the end idea when I said at 22:26:40.... There is a response, but after a loooong wait of 6 seconds. It's usually instantaneous.

Quote:
22:26:46.285356 IP 192.168.76.6.37569 > inflinux.site.telnet: S 30159679:30159679(0) win 5840 <mss 1460,sackOK,timestamp 31705988 0,nop,wscale 7>
At this point inflinux shows the login prompt from quadcore. I tried the same procedure several times and the delay is from nearly no time to endless in the worse case where I need to close the terminal window, open a new one and telnet again, possibly with no delay, 2 seconds delay 6 or 7 seconds... etc., delay. Once in session, I can run most commands quickly, but "ls" gives problems of delay some times (it hangs endlessly or just takes time to respond).

Hey!!!, just remembered, last time this happened seriously (worse than this, very loooong delays in ALL telnet logins, but no problem once in session), the ISP had done a change in DNS numbers. Once I put those in the linux boxes, all worked ok.

Please explain me how to make sudo ethtool to report "something" there where it shows null.

Greetings
 
Old 08-25-2008, 08:38 PM   #7
chort
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Your first box is having to do a lot of retransmits, and your second box has a phenomenal amount of incorrect TCP cookies received. It looks like the second box is having it's socket buffers overrun and generating TCP cookies, which for some strange reason your first box is apparently not answering correctly (bizarre). It seems like the second machine is having a hard time reading packets fast enough.

Is the second machine actually using eth0, or is the configured interface eth1? What happens if you try running ethtool against eth1?

I'm guessing the second machine has a very cheap NIC. Unless there's a problem with the configuration, your best bet is to buy a new NIC (the one it's using is probably integrated in the motherboard, right?) and use that instead. Intel made some very good 100Mb ethernet cards based on their 82555/82557/82559 chipsets. You can find them on eBay for ridiculously cheap (although pretty much no online stores sell them any more).
 
Old 08-26-2008, 04:47 PM   #8
energiza
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Location: Queretaro Mexico
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Posts: 51

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Yes both cards are integrated in the motherboard.
No there is no eth1 in the second machine.

I will go to the site and do some tests there.
Yes a new card will be a good thing.

Tell me about the 10% of all the packets to be invalid SYN cookies in TCPext:
Could this be just packets that pass by but don't belong or are not bound to this server?

Thanks
---

Instead of going to the site, I placed a cronjob to ping the card of the pc. Can't it be a DOS attack? Is it more likely the damn cheap card?:

Quote:
PING 192.168.76.15 (192.168.76.15) 56(84) bytes of data.
64 bytes from 192.168.76.15: icmp_seq=4 ttl=64 time=0.073 ms
64 bytes from 192.168.76.15: icmp_seq=5 ttl=64 time=0.045 ms
64 bytes from 192.168.76.15: icmp_seq=6 ttl=64 time=0.044 ms
64 bytes from 192.168.76.15: icmp_seq=7 ttl=64 time=0.049 ms
64 bytes from 192.168.76.15: icmp_seq=13 ttl=64 time=0.063 ms
64 bytes from 192.168.76.15: icmp_seq=14 ttl=64 time=0.064 ms
64 bytes from 192.168.76.15: icmp_seq=15 ttl=64 time=0.068 ms
64 bytes from 192.168.76.15: icmp_seq=16 ttl=64 time=0.075 ms
64 bytes from 192.168.76.15: icmp_seq=17 ttl=64 time=0.045 ms
64 bytes from 192.168.76.15: icmp_seq=18 ttl=64 time=0.052 ms
64 bytes from 192.168.76.15: icmp_seq=27 ttl=64 time=0.079 ms
64 bytes from 192.168.76.15: icmp_seq=28 ttl=64 time=0.043 ms
64 bytes from 192.168.76.15: icmp_seq=29 ttl=64 time=0.047 ms
64 bytes from 192.168.76.15: icmp_seq=38 ttl=64 time=0.077 ms
64 bytes from 192.168.76.15: icmp_seq=39 ttl=64 time=0.041 ms
64 bytes from 192.168.76.15: icmp_seq=40 ttl=64 time=0.051 ms
64 bytes from 192.168.76.15: icmp_seq=49 ttl=64 time=0.080 ms
64 bytes from 192.168.76.15: icmp_seq=50 ttl=64 time=0.043 ms

--- 192.168.76.15 ping statistics ---
50 packets transmitted, 18 received, 64% packet loss, time 48996ms
rtt min/avg/max/mdev = 0.041/0.057/0.080/0.016 ms
...lastly, the naked truth:

A ping to the main quadcore, from within this machine to it's own card:

Quote:
PING quadcore.site (192.168.76.6) 56(84) bytes of data.
64 bytes from quadcore.site (192.168.76.6): icmp_seq=1 ttl=64 time=0.019 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=2 ttl=64 time=0.009 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=3 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=4 ttl=64 time=0.007 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=5 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=6 ttl=64 time=0.009 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=7 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=8 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=9 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=10 ttl=64 time=0.007 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=11 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=12 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=13 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=14 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=15 ttl=64 time=0.007 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=16 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=17 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=18 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=19 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=20 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=21 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=22 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=23 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=24 ttl=64 time=0.007 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=25 ttl=64 time=0.007 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=26 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=27 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=28 ttl=64 time=0.008 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=29 ttl=64 time=0.009 ms
64 bytes from quadcore.site (192.168.76.6): icmp_seq=30 ttl=64 time=0.008 ms

--- quadcore.site ping statistics ---
30 packets transmitted, 30 received, 0% packet loss, time 28996ms
rtt min/avg/max/mdev = 0.007/0.008/0.019/0.003 ms

Last edited by energiza; 08-26-2008 at 08:10 PM.
 
  


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