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  • Redirect traffic to local address so iOS speedtest app measures LAN speed

    - by ivan_sig
    I have mounted a Speedtest Mini server on a local LAMP, so I can test my LAN speeds effortlessly just by opening the URL with a Flash enabled web browser, the thing is, I want my iOS and Android devices to test with the LAN server too, not with the WAN, as I'm trying to measure LAN-Only performance. Is there a way so I can redirect the traffic intended to an specific external IP (The one of the real server) to my local server?. I know the servers IP as a short Wireshark analysis gave me the data, but still searching for a way to make that redirect. I have Jailbreak and root on my devices, so playing with system files is not a problem. I've tried mounting a proxy and making redirects by the hosts file and domain names, but it looks like Ookla's app relies on IP address only.

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  • Weird WLAN connection

    - by tuelsch
    I assembled my first computer on my own. As I realised it had no WLAN (AsRock Z77 Extreme 4m) I bought a WLAN stick (ZyXel NWD 2105), plugged it in, started the setup from the CD and it worked, until I restarted the PC. That's when the problems started. The stick is able to connect to the router (P-660HN-F1Z) and the connection is stable, but not the internet access. In estimately 1 minute intervals there might be a short connection timeframe and dropbox or windows update are able to download some data, but as soon as I try to open a website the internet access is away. Note that the connection to the router does not shut down and remains stable at around 80-90%. The problem is definetly located on my pc, because with my laptop and phone the connection is stable and fast. Because I was so pissed off, I bought a EW-7612PIn V2 (PCI-E WLAN adapter), same problem. Now the weird thing is, if I don't use the PC for about 2 days, start it up, there is internet access (happened with both the stick and the PCI-E card). A bit slow, but it does not get away just like that, until I shut it down. Then, no matter how many times I restart, it won't come back. I googled a lot but now I'm at the end with my latin. Has anyone had a similar problem and resolved it? Technical details: Motherboard: AsRock Z77 Extreme 4M OS: Windows 7 professional 64bit Stick: Zyxel wireless N adapter NWD2105 PCI-E card: Edimax EW-7612PIn V2 Router: ZyXel P-660HN-F1Z Windows-IP-Konfiguration Hostname . . . . . . . . . . . . : xyz Primäres DNS-Suffix . . . . . . . : Knotentyp . . . . . . . . . . . . : Hybrid IP-Routing aktiviert . . . . . . : Nein WINS-Proxy aktiviert . . . . . . : Nein Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung 5: Medienstatus. . . . . . . . . . . : Medium getrennt Verbindungsspezifisches DNS-Suffix: Beschreibung. . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter # 3 Physikalische Adresse . . . . . . : 80-1F-02-61-C0-A6 DHCP aktiviert. . . . . . . . . . : Ja Autokonfiguration aktiviert . . . : Ja Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung 4: Verbindungsspezifisches DNS-Suffix: Beschreibung. . . . . . . . . . . : Edimax 802.11n Wireless Adapter Physikalische Adresse . . . . . . : 80-1F-02-61-C0-A6 DHCP aktiviert. . . . . . . . . . : Ja Autokonfiguration aktiviert . . . : Ja Verbindungslokale IPv6-Adresse . : fe80::38d2:f489:726d:1fb5%17(Bevorzugt) IPv4-Adresse . . . . . . . . . . : 192.168.1.41(Bevorzugt) Subnetzmaske . . . . . . . . . . : 255.255.255.0 Lease erhalten. . . . . . . . . . : Donnerstag, 15. November 2012 10:51:05 Lease läuft ab. . . . . . . . . . : Sonntag, 18. November 2012 10:51:18 Standardgateway . . . . . . . . . : 192.168.1.1 DHCP-Server . . . . . . . . . . . : 192.168.1.1 DHCPv6-IAID . . . . . . . . . . . : 578821890 DHCPv6-Client-DUID. . . . . . . . : 00-01-00-01-17-FF-D5-FE-BC-5F-F4-48-FC-4B DNS-Server . . . . . . . . . . . : 91.233.182.2 194.230.1.39 NetBIOS über TCP/IP . . . . . . . : Aktiviert Tunneladapter isatap.{263BEB98-344B-435C-888F-1B15B97C3AC1}: Medienstatus. . . . . . . . . . . : Medium getrennt Verbindungsspezifisches DNS-Suffix: Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0 DHCP aktiviert. . . . . . . . . . : Nein Autokonfiguration aktiviert . . . : Ja Tunneladapter Teredo Tunneling Pseudo-Interface: Verbindungsspezifisches DNS-Suffix: Beschreibung. . . . . . . . . . . : Teredo Tunneling Pseudo-Interface Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0 DHCP aktiviert. . . . . . . . . . : Nein Autokonfiguration aktiviert . . . : Ja IPv6-Adresse. . . . . . . . . . . : 2001:0:9d38:6ab8:209c:2944:3f57:fed6(Bevo rzugt) Verbindungslokale IPv6-Adresse . : fe80::209c:2944:3f57:fed6%11(Bevorzugt) Standardgateway . . . . . . . . . : :: NetBIOS über TCP/IP . . . . . . . : Deaktiviert C:\Users\xyz>ping 192.168.1.1 Ping wird ausgeführt für 192.168.1.1 mit 32 Bytes Daten: Antwort von 192.168.1.1: Bytes=32 Zeit=2ms TTL=254 Antwort von 192.168.1.1: Bytes=32 Zeit=2ms TTL=254 Antwort von 192.168.1.1: Bytes=32 Zeit=2ms TTL=254 Antwort von 192.168.1.1: Bytes=32 Zeit=2ms TTL=254 Ping-Statistik für 192.168.1.1: Pakete: Gesendet = 4, Empfangen = 4, Verloren = 0 (0% Verlust), Ca. Zeitangaben in Millisek.: Minimum = 2ms, Maximum = 2ms, Mittelwert = 2ms

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  • Two Network Adapters on Hyper-V Host - Best way to configure?

    - by GoNorthWest
    I have two physical network adapters installed in my Hyper-V host. I want one to be dedicated to the host, and the other to provide external network services to the VMs. Would the appropriate configuration be as such: Leave the first physical network adapter alone, assigning it the host IP, but not using it to create any Virtual Netorks For the second physical adapter, I would create an External Network, along with a Microsoft Virtual Switch, and use that to provide network services to the VMs. Each virtual NIC for the VM would be associated with that External Network. A static IP would be assigned to this adapter, and each VM would be assigned a static IP as well. The above seems reasonable to me, but I'm not sure if it's correct. Does anyone have any thoughts? Thanks! Mark

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  • Concurrent wireless and wired network

    - by Stew Megaw
    Hi, I am concerned with maintaining a wireless and wired network connection on my laptop. Basically I can change the metric on each interface so that Windows prefers one connection over the other. I am wondering is following scenario possible.... Some applications uses the wireless while other applications use the wired... I want Internet Explorer (only) to use the wireless connection while Outlook and everything else uses the wired connection. Perhaps adding some lines to the routing table might work? - Adding the ip addresses of websites I want to view via the wireless connection? Many Thanks in advance for any replies!

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  • Can't ping Ip over bridge

    - by tmn29a
    I'm unable to ping another host over a bridge I created, I can't see the error -.- It's a remote machine running debian stable with some backports for which I want to set up DHCP on the new Subnet 172.30.xxx.xxx to be used for KVM-Guests. ifconfig : bond0 Link encap:Ethernet HWaddr e4:11:5b:d4:94:30 inet addr:10.54.2.84 Bcast:10.54.2.127 Mask:255.255.255.192 inet6 addr: fe80::e611:5bff:fed4:9430/64 Scope:Link UP BROADCAST RUNNING MASTER MULTICAST MTU:1500 Metric:1 RX packets:34277 errors:0 dropped:0 overruns:0 frame:0 TX packets:18379 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2638709 (2.5 MiB) TX bytes:2887894 (2.7 MiB) br0 Link encap:Ethernet HWaddr f2:fc:4d:7f:15:f0 inet addr:172.30.254.66 Bcast:172.30.254.127 Mask:255.255.255.192 inet6 addr: fe80::f0fc:4dff:fe7f:15f0/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:252 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 B) TX bytes:10800 (10.5 KiB) Pings : ping -I br0 172.30.xxx.65 PING 172.30.xxx.65 (172.30.xxx.65) from 172.30.xxx.66 br0: 56(84) bytes of data. --- 172.30.xxx.65 ping statistics --- 3 packets transmitted, 0 received, 100% packet loss, time 2017ms ping -I bond0 172.30.254.65 PING 172.30.xxx.65 (172.30.xxx.65) from 10.54.2.84 bond0: 56(84) bytes of data. 64 bytes from 172.30.x.65: icmp_req=1 ttl=64 time=0.599 ms 64 bytes from 172.30.x.65: icmp_req=2 ttl=64 time=0.575 ms 64 bytes from 172.30.x.65: icmp_req=3 ttl=64 time=0.565 ms --- 172.30.x.65 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 1999ms rtt min/avg/max/mdev = 0.565/0.579/0.599/0.031 ms Route : Destination Gateway Genmask Flags Metric Ref Use Iface 172.30.x.64 * 255.255.255.192 U 0 0 0 br0 10.54.x.64 * 255.255.255.192 U 0 0 0 bond0 default 10.54.x.65 0.0.0.0 UG 0 0 0 bond0 default 172.30.x.65 0.0.0.0 UG 0 0 0 br0 The Interface : cat /etc/network/interfaces auto lo br0 iface lo inet loopback # Bonding Interface auto bond0 iface bond0 inet static address 10.54.x.84 netmask 255.255.255.192 network 10.54.x.64 gateway 10.54.x.65 slaves eth0 eth1 bond_mode active-backup bond_miimon 100 bond_downdelay 200 bond_updelay 200 iface br0 inet static bridge_ports bond0 address 172.30.x.66 broadcast 172.30.x.127 netmask 255.255.x.192 gateway 172.30.x.65 bridge_maxwait 0 If you need more info please ask. Thanks for your help !

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  • Why my router alows to connect to the internet only after plugging the cord to laptop?

    - by gennad
    Hi all! I'm using Ubuntu 10.10. I have D-link dir-320 wireless router. When I turn on my laptop Lenovo G555, I'm trying to connect to router by it's usually unsuccessful. But if I'll pull the ethernet cord from the router and insert it into my laptop, everything will work well. And if after that I'll pull the ethernet cord from the laptop and insert it into the router, my laptop connects to the router and it will have Internet access via wifi. How to make the laptop directly connects to the Internet after booting without switching the cord?

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  • Hard Disk based storage library

    - by Ryan M.
    We have a Tandberg T24 tape device to handle all of our long term backups right now. We decided that we're not backing up nearly everything that we would like to and that we still have a lot of vulnerabilities. To get to where we want to be, we're going to have to back up a lot more servers than we're currently doing. All of our internal servers have some sort of directly attached drive (I.e. LaCie Raid box or a simple portable hard drive) doing backups, but what we want to do is get those backups off-site. The current tape drive is directly attached via SCSI to a Windows Server 2008 File Server. So to back up anything to tape, it has to be funneled through the File Server. With the current increase that we have planned, I don't think that funneling everything through the File Server is the right course of action and I'm thinking that maybe a second backup device would be more appropriate. I would like your input on a couple of ideas. 1) Doing HDD instead of tape. Tape is hard to deal with. We have a regular rotation cycle, so they don't need years and years of shelf life, so I'm wondering if something HDD-based would be better. 2) Something accessible over the network. Instead of having the device directly attached to one specific machine, have it available to all the servers over the network. Our File Server is a 12-disk raid 6 set up.. I was thinking something like that, but with no raid involved, all disks are stand alone so they can be used/installed/removed on an individual basis. Does any such thing exist? Thanks for your ideas. I'm really interested to hear about some of the solutions you guys are using..

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  • Connecting to network device behind NAT from local LAN using the external port and IP

    - by lumbric
    I noticed at several different LANs connected to the Internet through a NAT the following phenomena. There is a server in the LAN and there is a port forwarding to reach this server also from outside the LAN through the NAT. E.g. consider a LAN with the address 192.168.0.* and a SSH server at 192.168.0.2 with port 22 and a forwarding from port 2222 at the NAT 192.168.0.1 to 192.168.0.2:22. If the NAT's external IP is 44.33.22.11, one can connect to the SSH server through 44.33.22.11:2222. Surprisingly this works only from outside the LAN. If one tries to connect to 44.33.22.11:2222 from behind the NAT, there is no answer. Of course one could simply use 192.168.0.2:22, but often it is simpler to use the external IP. The typical use case for me is the configuration on a laptop computer. Usually the user uses any arbitrary Internet connection to connect to his home or office server, but sometimes he will use also the LAN to connect to it and it would be annoying to have to different configurations or bookmarks. Why does it fail to connect from inside the LAN? Is there any good work around?

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  • After creating a mysql user with all privileges, the user cannot create databases in phpMyAdmin and only sees information_schema table

    - by GHarping
    This is a recurring problem for some reason... Using mysql 5.5, I am simply trying to create a user that can connect to the database remotely, have access to all databases, and create databases. I have created a user using: create user 'dev'@'%' identified by 'abcdefg'; then granted all permissions using: GRANT ALL ON *.* to 'dev'@'192.168.%' IDENTIFIED BY 'abcdefg' WITH GRANT OPTION; and the result is that the user cannot create databases, and can only see information_schema database for some reason. Databases Create database: Documentation No Privileges Database Ascending information_schema Total: 1 Does anyone know why this might be happening?

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  • No outbound internet connection after restarting CentOS 6.3

    - by wnstnsmth
    After restarting a headless CentOS 6.3 machine, it lost outbound internet connectivity, i.e. I can still connect to the server via SSH (ssh root@**.126.18.56), but stuff such as ping google.com gives google.com: unknown host, and yum list some_package gives a lot of network errors. This is what ifconfig gives: eth0 Link encap:Ethernet HWaddr 00:25:90:78:2D:5D inet addr:**.126.18.56 Bcast:**.126.18.255 Mask:255.255.255.0 inet6 addr: fe80::225:90ff:fe78:2d5d/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:75594 errors:0 dropped:0 overruns:0 frame:0 TX packets:787 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:7074741 (6.7 MiB) TX bytes:144391 (141.0 KiB) Interrupt:20 Memory:f7a00000-f7a20000 eth1 Link encap:Ethernet HWaddr 00:25:90:78:2D:5C UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) Interrupt:16 Memory:f7900000-f7920000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:6 errors:0 dropped:0 overruns:0 frame:0 TX packets:6 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:504 (504.0 b) TX bytes:504 (504.0 b) I have absolutely no clue how to debug this, and I find it very strange since I can still connect via ssh. EDIT: Weirdly, /etc/resolv.conf does not contain any entries, or none that I can make sense of: # Generated by NetworkManager search sui-inter.net # No nameservers found; try putting DNS servers into your # ifcfg files in /etc/sysconfig/network-scripts like so: # # DNS1=xxx.xxx.xxx.xxx # DNS2=xxx.xxx.xxx.xxx # DOMAIN=lab.foo.com bar.foo.com So is it possible that rebooting the server erased that file? It worked before at least! And how do I solve this? By the way, pinging an IP address works.

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  • Windows 7 can't identify network

    - by Carl Hörberg
    I use a Windows 7 machine to share my internet connection, but the one network interface which are connected to my local network is marked as "Unidentified network", the sharing works well anyway but because the interface can't be chosen as Home network i can't use the HomeGroup features etc. Do you know which requirements an interface has meet to identify a network in Windows 7?

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  • Inbound connections to a ubuntu machine running a VPN

    - by shanedowling
    Is it possible to open inbound connections to a machine connected to a VPN server? The machine is running ubuntu 9.10 with two network devices(a wireless card and ethernet port), I can connect to my machine locally using a local ip but when I try port forward using my router I can't connect from my external ip. Is there a way around this? I figure with 2 network devices I can vpn over one and use the other for inbound connections but I can't figure out how to do this. Thanks

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  • How can I determine which switch the Infiniband subnet manager is running on?

    - by ajdecon
    I recently inherited an Infiniband network containing multiple switches, and I know that one of these switches is running the subnet manager. The rest supposedly have that feature turned off, or were never enabled. The trouble is, I have no idea which one it is... I'd like to replace the switch subnet manager with OpenSM running on a couple of my infrastructure servers. Is there any way, short of logging into each switch individually, to determine which switch is running the SM?

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  • Identifying a CAT6 cable in a bundle

    - by Jon Tackabury
    We had a contractor wire up our office with all the cables leading back to a central location. The only problem is that he didn't label anything, so we have no idea which cables go to which room. One end of the cable is terminated in a wall-jack (in the rooms), the other end is un-terminated and will be punched to a patch panel. Is there a way to identify the cables without having to terminate them? We'd like to group the cables on the patch panel by room, but I don't want to crimp/punch each cable twice. Thanks!

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  • Windows 7 keeps asking for WIFI credentials

    - by RubenGeert
    If I want to log onto our WIFI network, Windows keeps asking for credentials. After many connection attempts (and sometimes some reboots) we finally manage to connect. Then the connection usually stays intact for the rest of the day. But it sometimes takes 15-20 minutes before we're online... Needless to say we're using a single username/password for all failing/succeeding attempts. Does anybody recognize these symptoms? How to troubleshoot this?

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  • Internet connection issues after installing Windows Phone 8 SDK

    - by Mosquito
    first of all I must admit, that I'm not good in all this network stuff. I am using Windows 8 OS. On my laptop (Lenovo G570) I have installed Windows Phone 8 SDK and shortly after this I started having weird issues with internet connection. When I start my laptop, internet usually works fine, but after a few minutes it starts slowing down so much, that I'm not able to open a single page. Rebooting doesn't work, after several disabling and enabling network adapter, it usually works again for a few minutes and then again it stops. I'm sure it has something to do with Windows Phone 8 SDK, because problems started with this. With SDK there was also installed "vEthernet (Internal Ethernet Port Windows Phone Emulator Internal Switch)" network adapter. It is worth to note that problems occur mostly in my school network, not at home. Both at home and school I am using Wi-Fi connection. I hope the information given are enough to help me. Thanks in advance for any answers!

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  • VMWare hypervisor with only 1 network card?

    - by Rafiq Maniar
    VMWare hypervisor minimum requirements states that the minimum network requirements is: one NIC, plus one for Management interface (source: http://www.vmware.com/products/datacenter-virtualization/vsphere-hypervisor/requirements.html) It used to be possible to use 1 NIC only. Is anybody using the new versions of VMWare in this configuration? I ask because my colo provider will only provide me with 1 uplink (my server does have 2 NICs). I need to be able to run the VMs and also have remote management using only 1 NIC. Possible?

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  • Two domains accessing same folder

    - by Liam Quinn
    I've just taken a new role in a school and am still familiarizing myself with their network, how ever I have recently been given a task and I'm having a little trouble finding out the fundementals of it. I have an admin network/domain 10.49.x.x and a classroom network/domian 192.168.1.x both connect to a Proxy server 10.49.202.231/192.168.1.51. Each domain has it's own shared folders as you'd expect, files and software installs etc, how ever there is a folder "staff" on the classroom network that all the teachers on the classroom network can access. The users on the admin network would like to access this same folder. How do I go about making this happen?

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  • Examples of applications where messages are guaranteed to turn up imediately

    - by James Hay
    I'm trying to find an example to show where data is sent from somewhere, whether manually or automatically, and is received IMMEDIATELY by the recipient, (doesn't matter whether we're talking mobile, desktop or whatever). An even better example would be where there were multiple recipients for the same message. It doesn't matter what the data is or the context it's used in, only the immediacy of receiving it. I was thinking that there might be some example in finance and the stock markets, but I haven't been able to find any through googling. IM clients are a great example of this and I think I'm basically looking for examples of applications that communicate over sockets. If anyone works on applications of this nature or knows of particular implementations, can you give me a quick run down of the use case and if it's commercial software the name of the software. This is all basically for research purposes so doesn't have to be particularly detailed. If anyone can help, thanks.

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  • Windows-7 Ultimate 64 bit wont connect to my wired/wireless networks.

    - by A302
    Windows 7 Ultimate 64 bit. Everything was working fine & then just stopped working. The nic card Realtek PCIe GBE Family Controller is enabled but does not connect to my router (cables & router ports are good). Wireless Atheros AR5007EG is enabled but the connection is limited (encryption type / key have been verified). A laptop running XP can connect both wired / wireless. SSID is not being broadcast, connect to network if it is not broadcasting is checked. Have checked services.msc for Bonjour & did not see it listed. Network & sharing center does not list any active networks. Device manager lists both devices as functioning properly. Router configuration has not been changed. Virus scan has not found anything. I would like to fix this rather than using Acronis to do a system restore. Thanks in advance for any advice offered in solving this. 26 Jan, the nic card & wireless are working using PCLinux OS Live CD. It appears that the problem is Windows 7 related.

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  • Can I split one ethernet line coming out of my wall into multiple separate lines?

    - by Burteçin 'Turk' Sapta
    Hi all and thanks in advance. I'll start with some background. I live in an apartment which provides internet service included in the rent. They use company called pavlov for the internet http://pavlovmedia.net/ wireless seems to be working fine but wired connection is at least %30 faster. Ethernet, cat5 outlet is built in the wall, and there is only 1 outlet in each room. I would like to take this 1 outlet coming out the wall and multiply it into 4 wires, for desktop, playstation, tv and laptop without loosing any internet bandwidth. i have absolutely no idea weather this line is coming from a switch or a router but i have been researching Ethernet splitter, routers, switches, hubs and haven't found a solid answer. what is the best solution for me? thank you once again! EDIT: ok this picture cleared few things http://www.home-network-help.com/images/home-network-expanded.jpg so seems that an ethernet switch is to ethernet as a USB hub is to USB. what is really 10/100Mbps Network Switch and what is the cap?

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  • Bypass network stack. Which options do we have? Pros and cons of each option [on hold]

    - by javapowered
    I'm writing trading application. I want to bypass network stack in Linux but I don't know how this can be done. I'm looking for complete list of options with pros and cons of each of them. The only option I know - is to buy solarflare network card which supports OpenOnLoad. What other options should I consider and what is pros and cons of each of them? Well the question is pretty simple - what is the best way to bypass network stack? upd: OpenOnload It achieves performance improvements in part by performing network processing at user-level, bypassing the OS kernel entirely on the data path. Intel DDIO to allow Intel® Ethernet Controllers and adapters to talk directly with the processor cache of the Intel® Xeon® processor E5. What's key difference between these techologies? Do they do roughly the same things? I much better like Intel DDIO because it's much easy to use, but OpenOnload required a lot of installation and tuning. If good OpenOnload application is much faster than good Intel DDIO application?

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  • What would cause my SendMail server not to acknowledge receiving a TCP Sequence?

    - by Mike B
    My TCP/IP Stack knowledge is a little rusty so please bear with me.... I have a CentOS 5.7 server with SendMail and am having seeing intermittent timeout issues sending email (particularly larger email) to other remote domains. It doesn't happen with all attachments or recipient domains. Just some. After some extended troubleshooting, I think I've narrowed it down to TCP Sequences not being acknowledged. Here's a breakdown of the TCP session from a packet capture I collected directly on my MTA (fooMTA): Packet 1 - 11: Standard TCP handshake followed by initial SMTP conversation. No errors. Packet #12 Recipient MTA: TCP sequence 231. Ack 91. Packet #13 FooMTA: TCP sequence 91. Ack 305. Packet #14 FooMTA: TCP sequence 1115. Ack 305. Packet #15 Recipient MTA: TCP sequence 305. Ack 2495. Packet #16 FooMTA: TCP sequence 2495. Ack 305. Packet #17 FooMTA: TCP sequence 5255. Ack 305. Packet #18: Recipient MTA: TCP sequence 305. Ack 5255. Packet #19: FooMTA: TCP sequence 6635. Ack 305. Packet #20: FooMTA: TCP sequence 8015. Ack 305. Packet #21: Recipient MTA: TCP Sequence 305. Ack 8015. Packet #22: FooMTA: TCP Sequence 10775. Ack 305. Packet #23: FooMTA: TCP Sequence 13535. Ack 305. Packet #24: Recipient MTA: TCP sequence 305. Ack 10775 Packet #25: FooMTA: TCP Sequence 14915. Ack 305 It keeps going like this with my server still thinking it hasn’t received sequence 305… in response the remote side eventually retransmits its prior data thinking that it never arrived. Eventually the gap gets so large that no new data is sent and the remote MTA keeps retransmitting old stuff. This contributes to an exponential backoff and eventually the remote side gives up. What’s strange to me is that I see the “missing” TCP sequence (305 in this case) arriving back to my server (via a packet capture collected directly from fooMTA) So I don’t get why my server keeps asking for it. Could this be firewall related? What would be the next step in troubleshooting?

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  • arp across subnets which devices can be detected?

    - by Gobliins
    i have some devices connected in the same physical network (LAN) but in different subnets. I want to detect them all with the ARP from my computer. My Computer is also in the same physical network but on a different subnet. ! The devices have no arp protocol installed (yet). Is it possible to detect the devices (with or withour ARP installed on every device)? If the devices have a MAC-address but no IP-address, can ARP still detect the machines?

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