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  • pfSense router on a LAN with two gateways

    - by JohnCC
    I have a LAN with an ADSL modem/router on it. We have just gained an alternative high-speed internet connection at our location, and I want to connect the LAN to it, eventually dropping the ADSL. I've chosen to use a small PFSense box to connect the LAN to the new WAN connection. Two servers on the LAN run services accessible to the outside via NAT using the single ADSL WAN IP. We have DNS records which point to this IP. I want to do the same via the new connection, using the WAN IP there. That connection permits multiple IPs, so I have configured pfSense using virtual IP's, 1:1 NAT and appropriate firewall rules. When I change the servers' default gateway settings to the pfSense box, I can access the services via the new WAN IPs without a problem. However, I can no longer access them via the old WAN IP. If I set the servers' default gateway back to the ADSL router, then the opposite is true - I can access the services via the ADSL IP, but not via the new one. In the first case, I believe this is because an incoming SYN packet arrives at the ADSL WAN IP, and is NAT'd and sent to the internal IP of the server. The server responds with a SYN/ACK which it sends via its default gateway, the pfSense box. The pfSense box sees a SYN/ACK that it saw no SYN for and drops the packet. Is there any sensible way around this? I would like the services to be accessible via both IPs for a short period at least, since once I change the DNS it will take a while before everyone picks up the new address.

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  • Cisco IOS BVI ACL: Only allow established UDP

    - by George Bailey
    Related: Cisco IOS ACL: Don't permit incoming connections just because they are from port 80 I know we can use the established keyword for TCP.. but what can we do for UDP (short of replacing a Bridge or BVI with a NAT)? Answer I found out what "UDP has no connection" means. DNS uses UDP for example.. named (DNS server) is lisenting on port 53 nslookup (DNS client) starts listening on some random port and sends a packet to port 53 of the server and notes the source port in that packet. nslookup will retry 3 times if necessary. Also the packets are so small that it does not have to worry about them coming in the wrong order. If nslookup receives a response on that port that comes from the servers IP and port then it stops listening. If the server tried to send two responses (for example a response and a response to the retry) then the server would not care if either of them made it because the client has the job to retry. In fact.. unless ICMP 3/3 packet gets through the server would not know about a failure. This is different from TCP where you get connection closed or timed out errors. DNS allows for an easy retry from the client as well as small packets.. so UDP is an excellent choice because it is more efficient. In UDP you would see nslookup sends request named sends answer In TCP you would see nslookup's machine sends SYN named's machine sends SYN-ACK nslookup's machine sends ACK and the request named's machine sends the response That is much more than is necessary for a tiny DNS packet

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  • Server resolve issues not consistent

    - by bobthemac
    I am having some weird issues with my web server. It has a public ip address and is set-up on an openVZ virtual machine. Accessing in to the site works fine every time but when trying to access out from the server I can't always connect out. Sometimes I can connect out and resolve addresses, sometimes I can't. The issue is visible in both ssh when trying to do a wget command on Google; sometimes it works and I get the index.html page and sometimes I get nothing. The issue is more visible in wordpress where you can't view themes but after a few presses of the try again button you can then view them. I have searched google and found nothing about this issue. Does anyone here have any ideas what could be causing this strange behaviour? Ports 80 and 2222 are open for web and ssh. Failed 17:26:33.398412 IP 86.148.184.124.38445 > 176.9.36.252.http: Flags [.], ack 98383, win 632, options [nop,nop,TS val 3070086 ecr 323106946], length 0 [email protected]..|. $..-.P..,.e......x....... .....B8. Passed 17:30:00.179630 IP 146.90.206.241.50091 > 176.9.36.252.http: Flags [F.], seq 1, ack 1, win 115, options [nop,nop,TS val 13740559 ecr 323308537], length 0 [email protected]... $....P.w...x.....s(K..... .....EK. Thanks in advance

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  • OpenSSL force client to use specific protocol

    - by Ex Umbris
    When subversion attempts to connect to an https URL, the underlying protocol library (openssl) attempts to start the secure protocol negotiation at the most basic level, plain SSL. Unfortunately, I have to connect to a server that requires SSL3 or TLS1, and refuses to respond to SSL or SSL2. I’ve done some troubleshooting using s_client and confirmed that if I let s_client start with the default protocol the server never responds to the CLIENT HELLO: $ openssl s_client -connect server.domain.com:443 CONNECTED(00000003) write:errno=104 --- no peer certificate available --- No client certificate CA names sent --- SSL handshake has read 0 bytes and written 320 bytes --- New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE --- Watching this in Wireshark I see: Client Server -------syn----------> <------ack----------- ---CLIENT HELLO-----> <------ack----------- [60 second pause] <------rst----------- If I tell s_client to use ssl2 the server immediately closes the connection. Only ssl3 and tls1 work. Is there any way to configure openssl to skip SSL and SSL2, and start the negotiation with TLS or SSL3? I've found the OpenSSL config file, but that seems to control only certificate generation.

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  • Java: Cleaning up what causes a connection reset

    - by Zombies
    There seems to be some confusion as well contradicting statements on various SO answers: http://stackoverflow.com/questions/585599/whats-causing-my-java-net-socketexception-connection-reset . You can see here that the accepted answer states that the connection was closed by other side. But this is not true, closing a connection doesn't cause a connection reset. It is cauesed by "an underlying TCP/IP error." What I want to know is if a SocketException: Connection reset means really besides "unerlying TCP/IP Error." What really causes this? As I doubt it has anything to do with the connection being closed (since closing a connection isn't an exception worthy flag, and reading from a closed connection is, but that isn't an "underlying TCP/IP error." My hypothesis is this Connection reset is caused from a server's failure to acknowledge an ACK packet (either wholly or just improperly as per TCP/IP). And that a SocketTimeoutException is generated only when no data is generated to be read (since this is thrown during a read after a certain duration, and read is waiting for data, but is not concerned with ACK packets). In other words, read() throws SocketTimeoutException if it didn't read any bytes of actual data (DATA LAYER) in its allotted time.

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  • SIP UAS asks for OPTIONS

    - by TacB0sS
    Hey, I have UAC that registers to a UAS, after registration the UAS sends me an OPTIONS request, what should I answer it? only the audio media streams? Update I: Allow me to explain myself better... if I want to invite someone to a session I USE the INVITE method and negotiate the media then, for that specific session. But once I register to the server, and it asks me for OPTIONS, then what should I supply, everything my client supports? once I answer it would it deduce that every INVITE I would request from now on would use these medias? or would I need to supply new media with every request? Update II: Hi Wiz, I was in the process of building a negotiation system, so i tried it out and replied the UAS here is the sort dialog we had: OPTIONS sip:[email protected] SIP/2.0 Via: SIP/2.0/UDP xx.xx.xx.xx:5060;branch=z9hG4bK45b197cb;rport=5060;received=xx.xx.xx.xx From: "Unknown" <sip:[email protected]>;tag=as66cf26df To: <sip:[email protected]> Contact: <sip:[email protected]> Call-ID: [email protected] CSeq: 102 OPTIONS User-Agent: Freeswitch 1.2.3 Max-Forwards: 70 Date: Sat, 05 Jun 2010 12:06:43 GMT Allow: INVITE,ACK,CANCEL,OPTIONS,BYE,REFER,SUBSCRIBE,NOTIFY,INFO Supported: replaces Content-Length: 0 OPTIONS In Response To 102: SIP/2.0 200 OK Via: SIP/2.0/UDP xx.xx.xx.xx:5060;branch=z9hG4bK45b197cb;rport=5060;received=xx.xx.xx.xx From: "Unknown" <sip:[email protected]>;tag=as66cf26df To: <sip:[email protected]> CSeq: 102 OPTIONS Call-ID: [email protected] Allow: INVITE,CANCEL,ACK,BYE,OPTIONS Content-Type: application/sdp Content-Length: 248 v=0 o=310 4515233118481497946 4515233118481497946 IN IP4 10.0.0.1 s=- i=Nu-Art Software - TacB0sS VoIP information c=IN IP4 10.0.0.1 m=audio 40000 RTP/AVP 0 8 101 a=rtpmap:0 PCMU/8000 a=rtpmap:8 PCMA/8000 a=rtpmap:101 telephone-event/8000 This response caused the server to stop sending me the options request, does this means I can only use these parameters with the server now? or as you said, it does not matter? Thanks, Adam.

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  • Anyone know exactly which JMS messages will be redelivered in CLIENT_ACKNOWLEDGE mode if the client

    - by user360612
    The spec says "Acknowledging a consumed message automatically acknowledges the receipt of all messages that have been delivered by its session" - but what I need to know is what it means by 'delivered'. For example, if I call consumer.receive() 6 times, and then call .acknowledge on the 3rd message - is it (a) just the first 3 messages that are ack'd, or (b) all 6? I'm really hoping it's option a, i.e. messages after the one you called acknowledge on WILL be redelivered, otherwise it's hard to see how you could prevent message lost in the event of my receiver process crashing before I've had a chance to persist and acknowledge the messages. But the spec is worded such that it's not clear. I get the impression the authors of the JMS spec considered broker failure, but didn't spend too long thinking about how to protect against client failure :o( Anyway, I've been able to test with SonicMQ and found that it implements (a), i.e. messages 'received' later than the message you call .ack on DO get redelivered in the event of a crash, but I'd love to know how other people read the standard, and if anyone knows how any other providers have implemented CLIENT_ACKNOWLEDGE? (i.e. what the 'de facto' standard is) Thanks Ben

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  • Java: Clearing up the confusion on what causes a connection reset

    - by Zombies
    There seems to be some confusion as well contradicting statements on various SO answers: http://stackoverflow.com/questions/585599/whats-causing-my-java-net-socketexception-connection-reset . You can see here that the accepted answer states that the connection was closed by other side. But this is not true, closing a connection doesn't cause a connection reset. It is cauesed by "an underlying TCP/IP error." What I want to know is if a SocketException: Connection reset means really besides "unerlying TCP/IP Error." What really causes this? As I doubt it has anything to do with the connection being closed (since closing a connection isn't an exception worthy flag, and reading from a closed connection is, but that isn't an "underlying TCP/IP error." My hypothesis is this Connection reset is caused from a server's failure to acknowledge an ACK packet (either wholly or just improperly as per TCP/IP). And that a SocketTimeoutException is generated only when no data is generated to be read (since this is thrown during a read after a certain duration, and read is waiting for data, but is not concerned with ACK packets). In other words, read() throws SocketTimeoutException if it didn't read any bytes of actual data (DATA LAYER) in its allotted time.

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  • Values are not returning from MY SQL database to my java class

    - by sam
    Hi, This is my Query DELIMITER $$ DROP PROCEDURE IF EXISTSdiscoverdb.getuser_info$$ # MySQL returned an empty result set (i.e. zero rows). `CREATE PROCEDURE discoverdb.getuser_info ( IN name VARCHAR(100), IN pass VARCHAR(100) ) BEGIN SELECT * FROM ad_user WHERE sLogin = name AND sPassHash=password(pass); END $$ # MySQL returned an empty result set (i.e. zero rows). DELIMITER ; This is my calling method public Authentication getAuthentication (String username,String password) { //TODO write your implementation code here: Authentication ack = new Authentication(); try{ String simpleProc = "{ call getuser_infosam(?,?)}"; java.sql.CallableStatement cs = con.prepareCall(simpleProc); cs.setString(1, username); cs.setString(2, password); java.sql.ResultSet rs = cs.executeQuery(); while (rs.next()) { System.out.println(rs.getString("sLogin")); System.out.println(rs.getString("sPassHash")); System.out.println(rs.getString("sForename")); System.out.println(rs.getString("sName")); System.out.println(rs.getString("company")); System.out.println(rs.getString("sEmail")); rs.close();} }catch ( Exception e) { e.printStackTrace(); System.out.print(e); } return ack; }

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  • Java: Cleaing up connection reset (but not by peer).

    - by Zombies
    There seems to be some confusion as well contradicting statements on various SO answers: http://stackoverflow.com/questions/585599/whats-causing-my-java-net-socketexception-connection-reset . You can see here that the accepted answer states that the connecteion was closed by other side. But this is not true, closing a connection doesn't cause a connection reset. It is cauesed by "an underlying TCP/IP error." What I want to know is if a SocketException: Connection reset means really besides "unerlying TCP/IP Error." What really causes this? As I doubt it has anything to do with the connection being closed (since closing a connection isn't an exception worthy flag, and reading from a closed connection is, but that isn't an "underlying TCP/IP error." My hypothesis is this Connection reset is caused from a server's failure to acknowledge an ACK packet (either wholly or just improperly as per TCP/IP). And that a SocketTimeoutException is generated only when no data is generated to be read (since this is thrown during a read after a certain duration, and read is waiting for data, but is not concerned with ACK packets). In other words, read() throws SocketTimeoutException if it didn't read any bytes of actual data (DATA LAYER) in its allotted time.

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  • ESXI Crash need help to understand log and support about nexentastor on virtual machine

    - by Bgnt44
    If i understand right, the following core dump means that the cpu4 has crashed the Host if i read the next line it seem that at the time the CPU 4 was assigned to the NexentaStore Vm ... SO if im right i can say that NexentaStor Vm crash my esxi Am i right ? Does that core dump can provide me some more informations ? 2012-11-14T03:48:01.046Z cpu4:6089)0x41221f25ba08:[0x41803007abff]PanicvPanicInt@vmkernel#nover+0x56 stack: 0x3000000008, 0x41221f25ba 2012-11-14T03:48:01.046Z cpu4:6089)0x41221f25bae8:[0x41803007b4a7]Panic@vmkernel#nover+0xae stack: 0x2e067c00000010, 0x0, 0x1f25bb38, 2012-11-14T03:48:01.047Z cpu4:6089)0x41221f25bc18:[0x4180300a7823]TLBDoInvalidate@vmkernel#nover+0x45a stack: 0xca, 0x0, 0x0, 0x0, 0x0 2012-11-14T03:48:01.047Z cpu4:6089)0x41221f25bc68:[0x418030489e17]UserMem_CartelFlush@<None>#<None>+0xce stack: 0xcaa0b, 0x0, 0x0, 0x4 2012-11-14T03:48:01.047Z cpu4:6089)0x41221f25bd78:[0x41803048ab91]UserMemUnmapStateCleanup@<None>#<None>+0x58 stack: 0x0, 0x41221f25bd 2012-11-14T03:48:01.047Z cpu4:6089)0x41221f25be58:[0x41803048b97d]UserMemUnmap@<None>#<None>+0x104 stack: 0x41221f267000, 0x41221f25bf 2012-11-14T03:48:01.048Z cpu4:6089)0x41221f25be98:[0x41803048bf20]UserMem_Unmap@<None>#<None>+0xe3 stack: 0x426, 0x0, 0x41221f25bef8, 2012-11-14T03:48:01.048Z cpu4:6089)0x41221f25beb8:[0x4180304a5985]UW64VMKSyscallUnpackReleasePhysMemMap@<None>#<None>+0x18 stack: 0x10 2012-11-14T03:48:01.048Z cpu4:6089)0x41221f25bef8:[0x418030476791]User_LinuxSyscallHandler@<None>#<None>+0x17c stack: 0x41803004cc70, 2012-11-14T03:48:01.048Z cpu4:6089)0x41221f25bf18:[0x4180300a82be]User_LinuxSyscallHandler@vmkernel#nover+0x19 stack: 0x3ffe63bed80, 0 2012-11-14T03:48:01.049Z cpu4:6089)0x41221f25bf28:[0x418030110064]gate_entry@vmkernel#nover+0x63 stack: 0x10b, 0x0, 0x0, 0x426, 0xcf76 2012-11-14T03:48:01.049Z cpu4:6089)VMware ESXi 5.1.0 [Releasebuild-799733 x86_64] PCPU 1 locked up. Failed to ack TLB invalidate (total of 1 locked up, PCPU(s): 1). 2012-11-14T03:48:01.050Z cpu4:6089)cr0=0x80010031 cr2=0xcaa0b750 cr3=0x197d7b000 cr4=0x42768 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:0 world:6111 name:"vmm0:Windows_2012_-_SQL" (V) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:1 world:6032 name:"vmm0:Windows_2012_-_AD" (V) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:2 world:6098 name:"vmm0:Windows_2012_-_App" (V) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:3 world:4099 name:"idle3" (IS) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:4 world:6089 name:"vmx-vcpu-0:NexentaStor" (U) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:5 world:6134 name:"vmm0:Ubuntu_-_NGINX" (V) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:6 world:4102 name:"idle6" (IS) 2012-11-14T03:48:01.050Z cpu4:6089)pcpu:7 world:4103 name:"idle7" (IS) 2012-11-14T03:48:01.050Z cpu4:6089)@BlueScreen: PCPU 1 locked up. Failed to ack TLB invalidate (total of 1 locked up, PCPU(s): 1).

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  • How do the Virtual machine network works ?

    - by Arpit
    I wish to know If I am using 2 VM instance on the same setup and I wish to use heavy data flow between the VMs is there any possibility that I get the Timeout (let say I having one timer on the sending end which stops on getting the ack.) I vague question is How network works in VM . I hope I am clear with the question.

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  • Proxy / Squid 2.7 / Debian Wheezy 6.7 / lots of TCP Timed-out

    - by Maroon Ibrahim
    i'm facing a lot of TCP timed-out on a busy cache server and here below my sysctl.conf configuration as well as an output of "netstat -st" Kernel 3.2.0-4-amd64 #1 SMP Debian 3.2.57-3 x86_64 GNU/Linux Any advice or help would be highly appreciated #################### Sysctl.conf cat /etc/sysctl.conf net.ipv4.tcp_tw_reuse = 1 net.ipv4.tcp_tw_recycle = 1 fs.file-max = 65536 net.ipv4.tcp_low_latency = 1 net.core.wmem_max = 8388608 net.core.rmem_max = 8388608 net.ipv4.ip_local_port_range = 1024 65000 fs.aio-max-nr = 131072 net.ipv4.tcp_fin_timeout = 10 net.ipv4.tcp_keepalive_time = 60 net.ipv4.tcp_keepalive_intvl = 10 net.ipv4.tcp_keepalive_probes = 3 kernel.threads-max = 131072 kernel.msgmax = 32768 kernel.msgmni = 64 kernel.msgmnb = 65536 kernel.shmmax = 68719476736 kernel.shmall = 4294967296 net.ipv4.ip_forward = 1 net.ipv4.tcp_timestamps = 0 net.ipv4.conf.all.accept_redirects = 0 net.ipv4.tcp_window_scaling = 1 net.ipv4.tcp_sack = 0 net.ipv4.tcp_syncookies = 1 net.ipv4.ip_dynaddr = 1 vm.swappiness = 0 vm.drop_caches = 3 net.ipv4.tcp_moderate_rcvbuf = 1 net.ipv4.tcp_no_metrics_save = 1 net.ipv4.tcp_ecn = 0 net.ipv4.tcp_max_orphans = 131072 net.ipv4.tcp_orphan_retries = 1 net.ipv4.conf.default.rp_filter = 0 net.ipv4.conf.default.accept_source_route = 0 net.ipv4.tcp_max_syn_backlog = 32768 net.core.netdev_max_backlog = 131072 net.ipv4.tcp_mem = 6085248 16227328 67108864 net.ipv4.tcp_wmem = 4096 131072 33554432 net.ipv4.tcp_rmem = 4096 174760 33554432 net.core.rmem_default = 33554432 net.core.rmem_max = 33554432 net.core.wmem_default = 33554432 net.core.wmem_max = 33554432 net.core.somaxconn = 10000 # ################ Netstat results /# netstat -st IcmpMsg: InType0: 2 InType3: 233754 InType8: 56251 InType11: 23192 OutType0: 56251 OutType3: 437 OutType8: 4 Tcp: 20680741 active connections openings 63642431 passive connection openings 1126690 failed connection attempts 2093143 connection resets received 13059 connections established 2649651696 segments received 2195445642 segments send out 183401499 segments retransmited 38299 bad segments received. 14648899 resets sent UdpLite: TcpExt: 507 SYN cookies sent 178 SYN cookies received 1376771 invalid SYN cookies received 1014577 resets received for embryonic SYN_RECV sockets 4530970 packets pruned from receive queue because of socket buffer overrun 7233 packets pruned from receive queue 688 packets dropped from out-of-order queue because of socket buffer overrun 12445 ICMP packets dropped because they were out-of-window 446 ICMP packets dropped because socket was locked 33812202 TCP sockets finished time wait in fast timer 622 TCP sockets finished time wait in slow timer 573656 packets rejects in established connections because of timestamp 133357718 delayed acks sent 23593 delayed acks further delayed because of locked socket Quick ack mode was activated 21288857 times 839 times the listen queue of a socket overflowed 839 SYNs to LISTEN sockets dropped 41 packets directly queued to recvmsg prequeue. 79166 bytes directly in process context from backlog 24 bytes directly received in process context from prequeue 2713742130 packet headers predicted 84 packets header predicted and directly queued to user 1925423249 acknowledgments not containing data payload received 877898013 predicted acknowledgments 16449673 times recovered from packet loss due to fast retransmit 17687820 times recovered from packet loss by selective acknowledgements 5047 bad SACK blocks received Detected reordering 11 times using FACK Detected reordering 1778091 times using SACK Detected reordering 97955 times using reno fast retransmit Detected reordering 280414 times using time stamp 839369 congestion windows fully recovered without slow start 4173098 congestion windows partially recovered using Hoe heuristic 305254 congestion windows recovered without slow start by DSACK 933682 congestion windows recovered without slow start after partial ack 77828 TCP data loss events TCPLostRetransmit: 5066 2618430 timeouts after reno fast retransmit 2927294 timeouts after SACK recovery 3059394 timeouts in loss state 75953830 fast retransmits 11929429 forward retransmits 51963833 retransmits in slow start 19418337 other TCP timeouts 2330398 classic Reno fast retransmits failed 2177787 SACK retransmits failed 742371590 packets collapsed in receive queue due to low socket buffer 13595689 DSACKs sent for old packets 50523 DSACKs sent for out of order packets 4658236 DSACKs received 175441 DSACKs for out of order packets received 880664 connections reset due to unexpected data 346356 connections reset due to early user close 2364841 connections aborted due to timeout TCPSACKDiscard: 1590 TCPDSACKIgnoredOld: 241849 TCPDSACKIgnoredNoUndo: 1636687 TCPSpuriousRTOs: 766073 TCPSackShifted: 74562088 TCPSackMerged: 169015212 TCPSackShiftFallback: 78391303 TCPBacklogDrop: 29 TCPReqQFullDoCookies: 507 TCPChallengeACK: 424921 TCPSYNChallenge: 170388 IpExt: InBcastPkts: 351510 InOctets: -609466797 OutOctets: -1057794685 InBcastOctets: 75631402 #

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  • How passively monitor for tcp packet loss? (Linux)

    - by nonot1
    How can I passively monitor the packet loss on TCP connections to/from my machine? Basically, I'd like a tool that sits in the background and watches TCP ack/nak/re-transmits to generate a report on which peer IP addresses "seem" to be experiencing heavy loss. Most questions like this that I find of SF suggest using tools like iperf. But, I need to monitor connections to/from a real application on my machine. Is this data just sitting there in the Linux TCP stack?

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  • triple duplicate acknowledgement in TCP congestion control

    - by Salvador Dali
    If this doesn't belong here, please tell me where is an appropriate place for such question. I am trying to understand ideas behind tcp congestion control mechanisms, and I am failing to understand why we need triple duplicate acknowledgement to trigger window change. In my opinion, double duplicate acknowledgement will be enough to get that the previous package is lost. So why we need the third ack?

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  • Why does TCP sometimes not acknowledge the packets it receives?

    - by misteryes
    I use firefox to visit a web server running on a computer on my LAN. I notice that sometimes TCP doesn't acknowledge the packets it receives. For example, in the following captured packets: https://docs.google.com/file/d/0B-LaBUj9KtQhS0RYNXF1RjZTa2M/edit?usp=sharing the 7th 9th and 11th packets are duplicated ACK, the browser receives TCP packets 6,8 and 10, but the browser TCP stack doesn't acknowledge the received packets, why?

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  • Streaming a large file

    - by Rich
    quick question say i wanted to download a file of considerable size 10gb say and i sent the GET request to a web server to download that file question is, if the client stopped reading the TCP connection, would the entire file still be downloaded, or does it depend on the client sending back an ack or something to the circuit asking for the next packet hope that makes sense This question was originally asked involving the Tor network, but i just want to know how a standard internet connection would handle this Thanks

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  • Need to capture and store receiver's details via IPN by using Paypal Mass Pay API

    - by Devner
    Hi all, This is a question about Paypal Mass Pay IPN. My platform is PHP & mySQL. All over the Paypal support website, I have found IPN for only payments made. I need an IPN on similar lines for Mass Pay but could not find it. Also tried experimenting with already existing Mass Pay NVP code, but that did not work either. What I am trying to do is that for all the recipients to whom the payment has been successfully sent via Mass Pay, I want to record their email, amount and unique_id in my own database table. If possible, I want to capture the payment status as well, whether it has been a success of failure and based upon the same, I need to do some in house processing. The existing code Mass pay code is below: <?php $environment = 'sandbox'; // or 'beta-sandbox' or 'live' /** * Send HTTP POST Request * * @param string The API method name * @param string The POST Message fields in &name=value pair format * @return array Parsed HTTP Response body */ function PPHttpPost($methodName_, $nvpStr_) { global $environment; // Set up your API credentials, PayPal end point, and API version. $API_UserName = urlencode('my_api_username'); $API_Password = urlencode('my_api_password'); $API_Signature = urlencode('my_api_signature'); $API_Endpoint = "https://api-3t.paypal.com/nvp"; if("sandbox" === $environment || "beta-sandbox" === $environment) { $API_Endpoint = "https://api-3t.$environment.paypal.com/nvp"; } $version = urlencode('51.0'); // Set the curl parameters. $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $API_Endpoint); curl_setopt($ch, CURLOPT_VERBOSE, 1); // Turn off the server and peer verification (TrustManager Concept). curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_POST, 1); // Set the API operation, version, and API signature in the request. $nvpreq = "METHOD=$methodName_&VERSION=$version&PWD=$API_Password&USER=$API_UserName&SIGNATURE=$API_Signature$nvpStr_"; // Set the request as a POST FIELD for curl. curl_setopt($ch, CURLOPT_POSTFIELDS, $nvpreq); // Get response from the server. $httpResponse = curl_exec($ch); if(!$httpResponse) { exit("$methodName_ failed: ".curl_error($ch).'('.curl_errno($ch).')'); } // Extract the response details. $httpResponseAr = explode("&", $httpResponse); $httpParsedResponseAr = array(); foreach ($httpResponseAr as $i => $value) { $tmpAr = explode("=", $value); if(sizeof($tmpAr) > 1) { $httpParsedResponseAr[$tmpAr[0]] = $tmpAr[1]; } } if((0 == sizeof($httpParsedResponseAr)) || !array_key_exists('ACK', $httpParsedResponseAr)) { exit("Invalid HTTP Response for POST request($nvpreq) to $API_Endpoint."); } return $httpParsedResponseAr; } // Set request-specific fields. $emailSubject =urlencode('example_email_subject'); $receiverType = urlencode('EmailAddress'); $currency = urlencode('USD'); // or other currency ('GBP', 'EUR', 'JPY', 'CAD', 'AUD') // Add request-specific fields to the request string. $nvpStr="&EMAILSUBJECT=$emailSubject&RECEIVERTYPE=$receiverType&CURRENCYCODE=$currency"; $receiversArray = array(); for($i = 0; $i < 3; $i++) { $receiverData = array( 'receiverEmail' => "[email protected]", 'amount' => "example_amount", 'uniqueID' => "example_unique_id", 'note' => "example_note"); $receiversArray[$i] = $receiverData; } foreach($receiversArray as $i => $receiverData) { $receiverEmail = urlencode($receiverData['receiverEmail']); $amount = urlencode($receiverData['amount']); $uniqueID = urlencode($receiverData['uniqueID']); $note = urlencode($receiverData['note']); $nvpStr .= "&L_EMAIL$i=$receiverEmail&L_Amt$i=$amount&L_UNIQUEID$i=$uniqueID&L_NOTE$i=$note"; } // Execute the API operation; see the PPHttpPost function above. $httpParsedResponseAr = PPHttpPost('MassPay', $nvpStr); if("SUCCESS" == strtoupper($httpParsedResponseAr["ACK"]) || "SUCCESSWITHWARNING" == strtoupper($httpParsedResponseAr["ACK"])) { exit('MassPay Completed Successfully: '.print_r($httpParsedResponseAr, true)); } else { exit('MassPay failed: ' . print_r($httpParsedResponseAr, true)); } ?> In the code above, how and where do I add code to capture the fields that I requested above? Any code indicating the solution is highly appreciated. Thank you very much.

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  • NVIDIA graphics driver on Macbook Pro 10,1

    - by Boatzart
    I just installed 14.04 over my old 12.04 partition on my Macbook Pro 10,1 (which is dual-booting with OS X) by following the instructions here. The only difference is that I'm using rEFInd instead of rEFIt. The proprietary NVIDIA drivers worked great with 12.04, but now I'm unable to boot into Unity with it in 14.04. Generally, I just get a black screen after the Grub menu, though occasionally I get some kind of panic screen like this, where I see errors like: [drm: __gen6_gt_force_wake_mt_get] *ERROR* Timed out waiting for forcewake old ack to clear. [drm: __gen6_gt_wait_for_thread_c0] *ERROR* GT thread status wait timed out [drm: __intel_ring_setup_status_page] *ERROR* render ring: wait for SyncFlush to complete for TLB invalidation timed out etc. Using the nouveau drivers works fine, but everything feels sluggish so I would really like to get the NVIDIA drivers working. Has anyone successfully gotten the NVIDIA drivers working with the GT-650M Mac Edition?

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  • Referring to hardware/software in first-person? [closed]

    - by JYelton
    At my company, there is a habit for the engineers to refer to their respective hardware/firmware/software in the first-person as if the device they are responsible for is a manifestation of themselves. I'll give you an example: Hardware Engineer: "I don't receive the first byte, so I stay off." Software Engineer: "I'm sending you the first byte after the ack flag, so I thought you were getting it." Hardware Engineer: "No, you're not turning me on." It was this very example I overheard today that nearly had me giggling in fits. "You're not turning me on." Well, I should hope not! So, is it common practice for engineers to do this, or simply unprofessional? Any suggestions for changing this apparently bad habit?

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  • Computer Networks UNISA - Chap 8 &ndash; Wireless Networking

    - by MarkPearl
    After reading this section you should be able to Explain how nodes exchange wireless signals Identify potential obstacles to successful transmission and their repercussions, such as interference and reflection Understand WLAN architecture Specify the characteristics of popular WLAN transmission methods including 802.11 a/b/g/n Install and configure wireless access points and their clients Describe wireless MAN and WAN technologies, including 802.16 and satellite communications The Wireless Spectrum All wireless signals are carried through the air by electromagnetic waves. The wireless spectrum is a continuum of the electromagnetic waves used for data and voice communication. The wireless spectrum falls between 9KHZ and 300 GHZ. Characteristics of Wireless Transmission Antennas Each type of wireless service requires an antenna specifically designed for that service. The service’s specification determine the antenna’s power output, frequency, and radiation pattern. A directional antenna issues wireless signals along a single direction. An omnidirectional antenna issues and receives wireless signals with equal strength and clarity in all directions The geographical area that an antenna or wireless system can reach is known as its range Signal Propagation LOS (line of sight) uses the least amount of energy and results in the reception of the clearest possible signal. When there is an obstacle in the way, the signal may… pass through the object or be obsrobed by the object or may be subject to reflection, diffraction or scattering. Reflection – waves encounter an object and bounces off it. Diffraction – signal splits into secondary waves when it encounters an obstruction Scattering – is the diffusion or the reflection in multiple different directions of a signal Signal Degradation Fading occurs as a signal hits various objects. Because of fading, the strength of the signal that reaches the receiver is lower than the transmitted signal strength. The further a signal moves from its source, the weaker it gets (this is called attenuation) Signals are also affected by noise – the electromagnetic interference) Interference can distort and weaken a wireless signal in the same way that noise distorts and weakens a wired signal. Frequency Ranges Older wireless devices used the 2.4 GHZ band to send and receive signals. This had 11 communication channels that are unlicensed. Newer wireless devices can also use the 5 GHZ band which has 24 unlicensed bands Narrowband, Broadband, and Spread Spectrum Signals Narrowband – a transmitter concentrates the signal energy at a single frequency or in a very small range of frequencies Broadband – uses a relatively wide band of the wireless spectrum and offers higher throughputs than narrowband technologies The use of multiple frequencies to transmit a signal is known as spread-spectrum technology. In other words a signal never stays continuously within one frequency range during its transmission. One specific implementation of spread spectrum is FHSS (frequency hoping spread spectrum). Another type is known as DSS (direct sequence spread spectrum) Fixed vs. Mobile Each type of wireless communication falls into one of two categories Fixed – the location of the transmitted and receiver do not move (results in energy saved because weaker signal strength is possible with directional antennas) Mobile – the location can change WLAN (Wireless LAN) Architecture There are two main types of arrangements Adhoc – data is sent directly between devices – good for small local devices Infrastructure mode – a wireless access point is placed centrally, that all devices connect with 802.11 WLANs The most popular wireless standards used on contemporary LANs are those developed by IEEE’s 802.11 committee. Over the years several distinct standards related to wireless networking have been released. Four of the best known standards are also referred to as Wi-Fi. They are…. 802.11b 802.11a 802.11g 802.11n These four standards share many characteristics. i.e. All 4 use half duplex signalling Follow the same access method Access Method 802.11 standards specify the use of CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) to access a shared medium. Using CSMA/CA before a station begins to send data on an 802.11 network, it checks for existing wireless transmissions. If the source node detects no transmission activity on the network, it waits a brief period of time and then sends its transmission. If the source does detect activity, it waits a brief period of time before checking again. The destination node receives the transmission and, after verifying its accuracy, issues an acknowledgement (ACT) packet to the source. If the source receives the ACK it assumes the transmission was successful, – if it does not receive an ACK it assumes the transmission failed and sends it again. Association Two types of scanning… Active – station transmits a special frame, known as a prove, on all available channels within its frequency range. When an access point finds the probe frame, it issues a probe response. Passive – wireless station listens on all channels within its frequency range for a special signal, known as a beacon frame, issued from an access point – the beacon frame contains information necessary to connect to the point. Re-association occurs when a mobile user moves out of one access point’s range and into the range of another. Frames Read page 378 – 381 about frames and specific 802.11 protocols Bluetooth Networks Sony Ericson originally invented the Bluetooth technology in the early 1990s. In 1998 other manufacturers joined Ericsson in the Special Interest Group (SIG) whose aim was to refine and standardize the technology. Bluetooth was designed to be used on small networks composed of personal communications devices. It has become popular wireless technology for communicating among cellular telephones, phone headsets, etc. Wireless WANs and Internet Access Refer to pages 396 – 402 of the textbook for details.

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  • Oracle NoSQL Database Exceeds 1 Million Mixed YCSB Ops/Sec

    - by Charles Lamb
    We ran a set of YCSB performance tests on Oracle NoSQL Database using SSD cards and Intel Xeon E5-2690 CPUs with the goal of achieving 1M mixed ops/sec on a 95% read / 5% update workload. We used the standard YCSB parameters: 13 byte keys and 1KB data size (1,102 bytes after serialization). The maximum database size was 2 billion records, or approximately 2 TB of data. We sized the shards to ensure that this was not an "in-memory" test (i.e. the data portion of the B-Trees did not fit into memory). All updates were durable and used the "simple majority" replica ack policy, effectively 'committing to the network'. All read operations used the Consistency.NONE_REQUIRED parameter allowing reads to be performed on any replica. In the past we have achieved 100K ops/sec using SSD cards on a single shard cluster (replication factor 3) so for this test we used 10 shards on 15 Storage Nodes with each SN carrying 2 Rep Nodes and each RN assigned to its own SSD card. After correcting a scaling problem in YCSB, we blew past the 1M ops/sec mark with 8 shards and proceeded to hit 1.2M ops/sec with 10 shards.  Hardware Configuration We used 15 servers, each configured with two 335 GB SSD cards. We did not have homogeneous CPUs across all 15 servers available to us so 12 of the 15 were Xeon E5-2690, 2.9 GHz, 2 sockets, 32 threads, 193 GB RAM, and the other 3 were Xeon E5-2680, 2.7 GHz, 2 sockets, 32 threads, 193 GB RAM.  There might have been some upside in having all 15 machines configured with the faster CPU, but since CPU was not the limiting factor we don't believe the improvement would be significant. The client machines were Xeon X5670, 2.93 GHz, 2 sockets, 24 threads, 96 GB RAM. Although the clients had 96 GB of RAM, neither the NoSQL Database or YCSB clients require anywhere near that amount of memory and the test could have just easily been run with much less. Networking was all 10GigE. YCSB Scaling Problem We made three modifications to the YCSB benchmark. The first was to allow the test to accommodate more than 2 billion records (effectively int's vs long's). To keep the key size constant, we changed the code to use base 32 for the user ids. The second change involved to the way we run the YCSB client in order to make the test itself horizontally scalable.The basic problem has to do with the way the YCSB test creates its Zipfian distribution of keys which is intended to model "real" loads by generating clusters of key collisions. Unfortunately, the percentage of collisions on the most contentious keys remains the same even as the number of keys in the database increases. As we scale up the load, the number of collisions on those keys increases as well, eventually exceeding the capacity of the single server used for a given key.This is not a workload that is realistic or amenable to horizontal scaling. YCSB does provide alternate key distribution algorithms so this is not a shortcoming of YCSB in general. We decided that a better model would be for the key collisions to be limited to a given YCSB client process. That way, as additional YCSB client processes (i.e. additional load) are added, they each maintain the same number of collisions they encounter themselves, but do not increase the number of collisions on a single key in the entire store. We added client processes proportionally to the number of records in the database (and therefore the number of shards). This change to the use of YCSB better models a use case where new groups of users are likely to access either just their own entries, or entries within their own subgroups, rather than all users showing the same interest in a single global collection of keys. If an application finds every user having the same likelihood of wanting to modify a single global key, that application has no real hope of getting horizontal scaling. Finally, we used read/modify/write (also known as "Compare And Set") style updates during the mixed phase. This uses versioned operations to make sure that no updates are lost. This mode of operation provides better application behavior than the way we have typically run YCSB in the past, and is only practical at scale because we eliminated the shared key collision hotspots.It is also a more realistic testing scenario. To reiterate, all updates used a simple majority replica ack policy making them durable. Scalability Results In the table below, the "KVS Size" column is the number of records with the number of shards and the replication factor. Hence, the first row indicates 400m total records in the NoSQL Database (KV Store), 2 shards, and a replication factor of 3. The "Clients" column indicates the number of YCSB client processes. "Threads" is the number of threads per process with the total number of threads. Hence, 90 threads per YCSB process for a total of 360 threads. The client processes were distributed across 10 client machines. Shards KVS Size Clients Mixed (records) Threads OverallThroughput(ops/sec) Read Latencyav/95%/99%(ms) Write Latencyav/95%/99%(ms) 2 400m(2x3) 4 90(360) 302,152 0.76/1/3 3.08/8/35 4 800m(4x3) 8 90(720) 558,569 0.79/1/4 3.82/16/45 8 1600m(8x3) 16 90(1440) 1,028,868 0.85/2/5 4.29/21/51 10 2000m(10x3) 20 90(1800) 1,244,550 0.88/2/6 4.47/23/53

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  • 13.10 suspend kills wifi

    - by ser
    i tried to post to this thread Hardware wireless switch has no effect after suspend and 13.10 upgrade for if i understand their question i am having the same problem but the answer option won't work for me and maybe i am not supposed to post there anyway, i dunno lol...ack when i come out of suspend, the wireless is disconnected with the only way to get it to reinitialize/be recognized is to do a full restart. at first i thought it was my gnome shell (for lock screen disappeared there with 13.10) but when i switched to the default ubuntu it's still doing it and it's kinda driving me nuts for i have to reopen all my files and browsers/tabs/windows everytime. i'm only a geekling so i don't know how to show the terminal stuff the above asker shows, but it sounds like the same issue and it only started with 13.10 upgrade a few days ago. any help would be much appreciated!!! thanks so much ser

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  • Paypal Sandbox Do Direct Payment Internal Error 10001 Timeout Processing Request

    - by user552968
    This is what I'm sending to https://api-3t.sandbox.paypal.com/nvp: VERSION = 65.0 SIGNATURE = AFcWxV21C7fd0v3bYYYRCpSSRl31AxdW2pQp.tWHTjGNcHflR-LJhJ0t USER = seller_1283487740_biz_api1.gmail.com PWD = 1283487748 AMOUNT = 50.00 CREDITCARDTYPE = Visa ACCT = 4031477440127509 EXPDATE = 12/2015 CVV2 =123 IPADDRESS = 127.0.0.1 METHOD = DoDirectPayment I can GetBalance, I can produce other errors when I intentionally send something wrong, but DoDirectPayment or DoAuthorization returns this: TIMESTAMP = 2010-12-24T03:35:10Z CORRELATIONID = 2ca329fdbe3c0 ACK = Failure L_ERRORCODE0 = 10001 L_SHORTMESSAGE0 = Internal Error L_LONGMESSAGE0 = Timeout processing request

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