Search Results

Search found 9758 results on 391 pages for 'wireless networking'.

Page 166/391 | < Previous Page | 162 163 164 165 166 167 168 169 170 171 172 173  | Next Page >

• CentOS Client - Unable to Establish iSCSI connection with multiple interfaces on the initiator

  - by slashdot

  So after upgrading to CentOS 6.2, I am seemingly no longer able to login into my iSCSI targets. I have multiple interfaces on different subnets on the system, and I first thought that it had to do with the fact that I may not be binding correct interfaces, which seems to be the case when looking at netstat, as this is clearly wrong: [root]? netstat -na|grep .90 tcp 0 1 10.10.100.60:42354 10.10.8.90:3260 SYN_SENT tcp 0 1 10.10.100.60:40777 10.10.9.90:3260 SYN_SENT I then went ahead and disabled all but one interface, and so as a result netstat appears to be correct, but the issue with login remains. I am positive that the target never sees a packet, because I see nothing by SYN_SENT. I know the problem is on my client, because the target is servicing multiple systems, none of which are CentOS 6.2. At this point I am pretty confident that some things changed between CentOS 6.0/6.1 and 6.2. So, if anyone have any thoughts, or ran into this, I would very much like to hear your thoughts. [root]? iscsiadm --mode node --targetname iqn.2011-12.dom.homer:01:lab-centos-servers-00001 --portal 10.10.8.90:3260,2 --interface=sw-iscsi-0 --login Logging in to [iface: sw-iscsi-0, target: iqn.2011-12.dom.homer:01:lab-centos-servers-00001, portal: 10.10.8.90,3260] (multiple) iscsiadm: Could not login to [iface: sw-iscsi-0, target: iqn.2011-12.dom.homer:01:lab-centos-servers-00001, portal: 10.10.8.90,3260]. iscsiadm: initiator reported error (8 - connection timed out) iscsiadm: Could not log into all portals [root]? netstat -rn Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 10.10.8.0 0.0.0.0 255.255.255.0 U 0 0 0 eth2.7 10.10.9.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3.7 10.10.100.0 0.0.0.0 255.255.252.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth2 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth3 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth2.7 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth3.7 0.0.0.0 10.10.100.1 0.0.0.0 UG 0 0 0 eth0 Output of ip addr show for the two interfaces involved: [root]? for i in 2.7 3.7; do ip addr show eth$i; done 6: eth2.7@eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP link/ether 00:0c:29:94:5b:8d brd ff:ff:ff:ff:ff:ff inet 10.10.8.60/24 brd 10.10.8.255 scope global eth2.7 inet6 fe80::20c:29ff:fe94:5b8d/64 scope link valid_lft forever preferred_lft forever 7: eth3.7@eth3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP link/ether 00:0c:29:94:5b:97 brd ff:ff:ff:ff:ff:ff inet 10.10.9.60/24 brd 10.10.9.255 scope global eth3.7 inet6 fe80::20c:29ff:fe94:5b97/64 scope link valid_lft forever preferred_lft forever Update 01/06/2012: This issue is getting even more interesting by the day it seems. I went a few weeks back and grabbed a snapshot of this system from before upgrading to 6.2. I spun up a new system from the snapshot, and reconfigured interface info and host keys, as well as iSCSI initiator and iscsi interface info to match new MACs. Changed nothing else. Then, I attempted to connect to my targets, and no issues at all. I cannot say that this was unexpected. I then went ahead and compared sysctl settings from both systems and there were differences after the upgrade, but nothing seemingly relevant to iSCSI or IP that could contribute to this. I also noticed that by default now two sessions per connection were enabled after the upgrade, but I changed it back to 1 session in /etc/iscsi/iscsid.conf. On the problematic system we can see that source interface is seemingly wrong, but even when I disable the 10.10.100 interface, problems persist. So, while this may be relevant, I could not validate it for certain. Needless to say, further research is necessary. Something is clearly different between releases. Working system is on 6.1, and non-working is 6.2. ::Working System:: tcp 0 0 10.10.8.210:39566 10.10.8.90:3260 ESTABLISHED tcp 0 0 10.10.9.210:46518 10.10.9.90:3260 ESTABLISHED [root]? ip route show 10.10.8.0/24 dev eth2.6 proto kernel scope link src 10.10.8.210 10.10.9.0/24 dev eth3.7 proto kernel scope link src 10.10.9.210 10.10.100.0/22 dev eth0 proto kernel scope link src 10.10.100.210 169.254.0.0/16 dev eth0 scope link metric 1002 169.254.0.0/16 dev eth2.6 scope link metric 1006 169.254.0.0/16 dev eth3.7 scope link metric 1007 default via 10.10.100.1 dev eth0 ::Non-working System:: tcp 0 1 10.10.100.60:44737 10.10.9.90:3260 SYN_SENT tcp 0 1 10.10.100.60:55479 10.10.8.90:3260 SYN_SENT [root]? ip route show 10.10.8.0/24 dev eth2.6 proto kernel scope link src 10.10.8.60 10.10.9.0/24 dev eth3.7 proto kernel scope link src 10.10.9.60 10.10.100.0/22 dev eth0 proto kernel scope link src 10.10.100.60 169.254.0.0/16 dev eth0 scope link metric 1002 169.254.0.0/16 dev eth2.6 scope link metric 1006 169.254.0.0/16 dev eth3.7 scope link metric 1007 default via 10.10.100.1 dev eth0 And the result is still same: [root]? iscsiadm: Could not login to [iface: sw-iscsi-0, target: iqn.2011-12.dom.homer:01:lab-centos-servers-00001, portal: 10.10.8.90,3260]. iscsiadm: initiator reported error (8 - connection timed out) iscsiadm: Could not login to [iface: sw-iscsi-1, target: iqn.2011-12.dom.homer:02:lab-centos-servers-00001, portal: 10.10.9.90,3260]. iscsiadm: initiator reported error (8 - connection timed out) iscsiadm: Could not log into all portals Update 01/08/2012: I believe I have been able to figure out the answer to my issue. It is quite obscure and I doubt this will happen to anyone else any time soon. It turns out that setting iface.iscsi_ifacename and iface.hwaddress in the interfaces configuration file is not legal. When one manually adds an iscsi target, such as below, all settings from the interface config file are copied into the node config file, that gets created by the below command. Result is parameters iface.iscsi_ifacename and iface.hwaddress together in the same config file. These parameters are seemingly mutually exclusive, which does not exactly make sense, or there is perhaps an oversight in the codepath. Perhaps I will investigate further. # iscsiadm -m node --op new -T iqn.2011-12.dom.homer:01:lab-centos-servers-00001 -p 10.10.8.90,3260,2 -I sw-iscsi-0 # iscsiadm -m node --op new -T iqn.2011-12.dom.homer:02:lab-centos-servers-00001 -p 10.10.9.90,3260,2 -I sw-iscsi-1 Notice, below I commented out iface.hwaddress and iface.ipaddress, after which I re-added targets, with same command as above. All works just fine. [root]? cat * # BEGIN RECORD 2.0-872.33.el6 iface.iscsi_ifacename = sw-iscsi-0 iface.net_ifacename = eth2.6 #iface.hwaddress = XX:XX:XX:XX:XX:XX #iface.ipaddress = 10.10.8.60 iface.transport_name = tcp iface.vlan_id = 6 iface.vlan_priority = 0 iface.iface_num = 0 iface.mtu = 0 iface.port = 0 # END RECORD # BEGIN RECORD 2.0-872.33.el6 iface.iscsi_ifacename = sw-iscsi-1 iface.net_ifacename = eth3.7 #iface.hwaddress = XX:XX:XX:XX:XX:XX #iface.ipaddress = 10.10.9.60 iface.transport_name = tcp iface.vlan_id = 7 iface.vlan_priority = 0 iface.iface_num = 0 iface.mtu = 0 iface.port = 0 # END RECORD Again, chances of this happening to someone else are slim to none, so likely waste of time typing this up. But, if someone does encounter this issue, I hope this post will help.

  Read the article

• Problems with RDC into Win2008 Server

  - by Jason

  I'm having the same problem with a variety of new machines that I have built. When I RDC into the machine, the display does not update correctly. I get partial images, or refreshes only every 20-30 seconds. It is completely unusable. Eventually, it will even disconnect even though I am logged in. From RDCing into the machine, it looks like the machine is down, but it is fine. I can connect to it with an monitor and the problem is not visible. I think it is a problem with my network configuration. What should I look for to resolve this?

  Read the article

• wmware fusion 5.0.1, LAN, disconnecting from server [closed]

  - by Maxim

  Currently I am using : OSX 10.7.5 VMWare:5.0.1 with windows 7 professional Problem: Getting disconnected from LAN game. Description: 4 of us are trying to play frozen throne on the same network. The thing is, they are all running windows computers, and I am running W7 on VMware. I haven't made any adjustments other than changing from "sharing internet with my mac" to Bridged network "autodetect". When we start to play, everything works then all of a sudden I get disconnected. This happens every once in a while, the timing differs from time to time. None of the others ever disconnects. What could be the problem? Thanks for the help!

  Read the article

• How can I use Windows Firewall to only permit the Windows Update service to make an outbound connection?

  - by microsmash

  I'm trying to tailor my Windows Firewall settings (using the Windows Firewall with Advanced Security console) to only permit programs that need to access the Internet with an outbound connection to do so. This works fine for normal applications as I can just allow the program, but services that load in the svchost.exe process are a problem. The only services I actually need to give access to are Windows Update and the Background Intelligent Transfer Service (and even that, I would only like Windows Update to be able to submit jobs to, but that's another issue.) Is there a method to only allow these to be permitted an outbound connection, and not any of the other services loaded in svchost?

  Read the article

• Can I set up OpenVPN on two or more machines so that they can each act as client and server?

  - by ianfuture

  The question summarises what I want to achieve. In more detail: I have a Windows XP Pro PC at a work location that I want to be able to access my home Windows XP Pro PC and other home computers from. But I also want to be able to connect to the work PC from home. I think the term generally used is a "mesh" network. Can I do this with OpenVPN ? If so how would I do it? What are the most important things to remember to do? EDIT: The work Windows XP Pro PC is largely managed by IT Dept, I do have local admin rights to install things. Some settings are disabled. My main concern was firewalls and port forwarding on the work PC. Any suggestions?

  Read the article

• What's Switched LAN Topology ?

  - by mgpyone

  If somebody can tell me clearly what "Switched LAN Topology"is, it'll be great. I can't even understand what it's due to the following picture . Any answers are most welcome.

  Read the article

• How to connect a VM running on an ESXi host to that host via a VMKernel NIC?

  - by Zac B

  Say I have an ESXi (5.0) host that runs a Linux distribution which hosts iSCSI targets, which contain the images for other VMs which the host will run. When it's used, I'll start the host first, then the iSCSI server, and then refresh all storage targets/HBAs in order to see the provided shares as online. I know it's a strange puzzle-box solution, but I was told to implement it. The ESXi host itself has a gigabit NIC which connects to the outside world. The guest OS (CentOS) supports VMXNet3, however, and if I can, I'd like to use its VMXNET3 NIC to host iSCSI for the ESXi host. How should I go about doing this? I went to create a new virtual network, and selected "VKernel", as it suggested that I use that type of network for SAN traffic, but it is apparently not set up for "self-hosted" SAN hosts, as the new network did not appear as an option to attach the CentOS box's VMXNET3 NIC to. How should I best connect an iSCSI host out to its "parent" ESXi host, if I need a) a 10gb connection, and (optionally) b) a VMKernel network for it?

  Read the article

• Set up WLAN in 3-level house

  - by Balint Erdi

  I'm having a hard time setting up the network in our house. It has three levels (basement, ground floor, first level). The WLAN is set up by an ASUS RT-N12 router which provides perfect coverage for the ground floor and the basement. However, I set up my "home office" in the basement where the signal barely arrived. So I purchased a TP-Link TL-WA901ND (300 Mbps) Access Point which I set up in the other corner of the ground floor to expand the ASUS router's range. I used the AP's Repeater mode for that. The distance between my computer and the TP-Link AP is 6-7 meters. There is a staircase going down from the ground floor to the basement so there are no solid walls between the computer and the AP. This setup mostly works (I am writing this from the basement) but it is not reliable (the signal strength sometimes goes down to ~40% of the max) sometimes so I wonder if I am doing it correctly or if there is a better way. Screenshot of the router's and the AP's dashboard screen follow: Any comments on what I am doing wrong or hints for improvement are appreciated. Thank you. UPDATE Tried one more thing, setting up the TP-LINK AP in Access Point mode. That way, I can make it use a different SSID. I enabled WDS/Bridge so that it expands the range of the ASUS router (see screenshot). That does not work, either, if I connect to the network set up by the TP-LINK device (PELSTER-2), I can't reach the external network (the Internet). It seems the problem always comes back to this, the TP-LINK does not have access to the external network, whatever its mode of operation.

  Read the article

• How to discover if a specific address/port is reachable?

  - by marco.ragogna

  I need a simple utility that allow me to check if a PC, attached to a local network, is able to reach a specified address:port using specified protocol like TCP or UDP Machine's OS I will use to do the check is Windows XP. Can you help me, please?

  Read the article

• TCP/IP Forwarding in Windows Vista and Above

  - by Charles Gargent

  This is the way to do it on XP, but is it possible on Windows Vista and Above? If so how do you detect it? Is there a registry setting for it, or is there com dll or api for it?

  Read the article

• On a Mac, how are connections (possibly by spyware) made to outside internet addresses during initia

  - by TT

  I am trying to secure a Mac after discovering that network links are being established to some unwanted internet sites. Using 'lsof -i' (list open 'files', internet) I have seen that launchd, ntpd, firefox, dropbox and other processes are either 'LISTENING' or have 'ESTABLISHED' links to a site or sites which I suspect have to do with spyware. I have been trying to find startup files and preference lists that initiate thise links but can't find them. I could easily reinstall the OS and restore data from a backup but I'd prefer to know how to fix this as I have six Macs to look after. Thanks...

  Read the article

• What is the equivalent of 127.255.255.255 for OS/X machines so I can test broadcast udp packets without a network?

  - by JohnPristine

  I am trying to test my program that makes use of broadcast UDP (not multicast!). In Linux, I can use the 127.255.255.255:64651 address and everything works beautifully, in other words, I send a packet to 127.255.255.255:64651 and multiple clients listening on that port get the packet. A real broadcast example! Unfortunately on my OS/X machine (Mountain Lion) the same example does not work. Is there any way I can get 127.255.255.255 to work on mac machines? Any other solution to get broadcast working on my mac machine without a network? Note: It has to be broadcast, not multicast.

  Read the article

• Confusion about TCP packet analysis terms

  - by Berkay

  I'm analyzing our network and have some confusion about the terms: this is the 2-packet output from source to destination. from these i have to get some features as describe, pls make me clear... packets with at least a bytes of TCP data payload: it seems tcp.len0; The minimum segment size (confusion is headers are included or or not) The average segment size observed during the lifetime of the connection, the definition: is calculated as the value reported in the actual data bytes divided by the actual data pkts reported. Total bytes in IP packets, should be ip_len value. Total bytes in (Ethernet) The total number of bytes sent probably related to frame.len and frame.cap_len these two terms are describes as, also make me clear about these two terms. frame.cap_len: Frame length stored into the capture file frame.len: Frame length on the wire

  Read the article

• Internet not working on a VirtualBox Linux machine

  - by mtahmed

  I installed VirtualBox on a Windows 7 PC and installed Xubuntu (Ubuntu with XFCE) on it. Now on the Windows, I am connected to the internet through a LAN which automatically authenticates to connect to the network(because its my work computer). I have also installed the guest additions on this virtual machine (Xubuntu). I tried both NAT and bridging to set up internet connection but I still cannot connect to the internet. For NAT: The browser doesn't say website not found but it keeps trying to load it forever and the network status monitor (the one provided by VirtualBox) doesn't show any green light (no incoming packets). For Bridging: Same as for NAT but the network status monitor shows incoming packets and outgoing packets. But internet still doesn't work. I tried a lot of different things but none worked.

  Read the article

• Vista: "connect to a network" does not load (can't set up VPN)

  - by Arkaaito

  I'm trying to connect to my office VPN from home. One small problem: my home desktop uses Vista (64-bit, Ultimate edition). On Vista, you're supposed to set up a VPN like so: Open the control panel Click on Network Click on "Connect to a Network" Configure a new connection of type "Office" The problem is, when I click on the link for "Connect to a Network", nothing happens. Can anyone suggest how I should go about troubleshooting this? (Or am I better off just upgrading to Windows 7?)

  Read the article

• ProCurve 1800 switch issue

  - by user98651

  I recently deployed ProCurve 1800-24G switches in place of some older ProCurve 2424M switches in my network. However, I'm having a serious problem with the switch connected to the router. It seems, every night when our Windows 2008 R2 server (off site) runs a backup to a iSCSI target (on site) [facilitated through a PPTP tunnel] the LAN loses connectivity with the router. To clarify, there is only one router which is connected to the switch affected by this problem. The only way to resolve the issue is to either reboot the router or pull the ethernet cable that goes to the router and plug it back in. During the outage, clients cannot receive DHCP requests, DNS requests, ping, or do anything else with the router in this state. Now, neither the switch or router are configured extensively and the issue only seems to have surfaced with the new switch in place. I have tried a number of things including replacing cables, rebooting and checking the switch configuration (it is literally as basic as you can get at this point-- flat LAN, no trunking). Interestingly, the router shows (accessed externally) no changes in configuration or status during this state but similarly cannot ping or access other hosts on the network. This issue occurs in different stages of backup (ie, different amounts transferred). I've also dumped packets from the switch into WireShark but cannot seem to find any anomaly yet (I'm looking at packets around the time the issue appeared and at the time when I reset the NIC). Any suggestions for what to look for? Ideas on what could be causing this? I'm seeing some transmit/receive errors on the NIC from both the router and switch side but nothing serious when compared to the total packet counts. I'm seriously doubting hardware at this point, as I have tried another switch, different cables, and a different NIC on the router.

  Read the article

• Cannot browse network shares in Windows Explorer, but paths are still accessible

  - by Jeff Lockhart

  Windows Explorer has somehow corrupted itself and I'm not sure how to fix this problem. My Windows installation has been in use for a few years with network shares setup and working. Recently, I noticed that a program that I use to save network share paths to a database was no longer opening the explorer window to browse the path. It usually opens to the last path saved, but now it was just not opening at all. When I go to Windows Explorer to browse the network share directly, I get the error \\SERVER is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions. The specified network provider name is invalid. The network shares are just shares on the server itself (once saved to the database, they're used on the server as well as clients to reach files). The strange thing is, the files are still accessible from the program that uses them if I type the network share path in manually. So it is only a problem with Windows Explorer browsing the path. The reason I think there is some sort of configuration or setting, possibly in the registry, corrupted is that when the problem first manifest itself, I was somehow able to open an explorer window to a network share path, but the breadcrumb in the address bar did not function properly. It duplicated the share name folder at the top of the breadcrumb stack and when I clicked the second of the duplicated share folder, it crashed explorer.exe. I haven't been able to browse any network share path since this happened. I have tried using the IP address directly \\192.168.1.# as well as \\localhost and neither of those work either. I have tried running sfc /scannow and it did not find any errors. I tried ipconfig /flushdns and this made no difference. Attempting to map the network share to a drive fails using either the explorer GUI or net use command. Is there some way to reset Windows Explorer somehow to resolve this? I'd really like to avoid reinstalling Windows entirely if I can.

  Read the article

• What type of VPS stats should I look for?

  - by Dave

  I have a few websites that average a total of 10,000 uniques a day across my network. I also have a few mobile apps that pull xml data maybe 5,000 calls a day. My sites aren't anything major just a few wallpaper websites and few other small sites, nothing real database intensive. I currently own a dedicated server and I feel like it's overkill for my network. I'm looking into getting a Virtual Private Server (VPS). I was just wondering what kind of stats I should be looking for to support my network of sites. Thanks

  Read the article

• Why does just splitting an Ethernet cable not work?

  - by Sin Jeong-hun

  I thought the Ethernet is logically a one-line communication bus (for argument's sake, I am excluding hubs). All machines attached on the bus hears the same signals and the machines themselves try to avoid collisions by randomly backing off. http://computer.howstuffworks.com/ethernet6.htm If so, why would splitting one Ethernet line from my home router into two and connecting two computers not work? Why do I have to add a switch to it? *What the Internet said would not work. [4 port home router] ------[one Ethernet cable]-----[simple splitter]======[two computers] *What the Internet said I should do [4 port home router] ------[one Ethernet cable]-----[switch]======[two computers] Is this because of the signal degradation (reduced electric current)? Thank you for all the answers! The reason why I did not just use the two ports of my home router is... The 4-port gigabit router is in my room, and I had put a computer in another room (also my room, though). Since a wired network is far more reliable and secure, I had bought a long Ethernet cable and and connected the computer to the router. Now I was thinking about adding another computer to that room. I could buy another long Ethernet cable, but then there will be two cables between the rooms. The one line already is a minor annoyance, so I thought if I could share the one line between the two computers in that room. A switch would work, but it requires power and is a little bit pricey. That is why I wondered why it would not work to simply split the physical Ethernet cable. Apparently I do not completely understand how Ethernet and a switch work. I just have some bit of knowledge I heard in my college class.

  Read the article

• CentOS listen to everything on the wire

  - by Poni

  I know there's a native command on linux that will output (to stdout) every "event" related to a certain network interface (be it eth0 etc'). Like there's tail -f <file> to listen on file changes.. I just can't find it. I want to see all events, incoming packets, even dropped ones. At lowest level possible. In every protocol (TCP, UDP etc'). I think WireShark is a bit too big for this as I need something very simple just to see the events, it's for testing. What's the command?

  Read the article

• How to share a USB modem?

  - by allenskd

  Usually I wouldn't have this problem if it was a dsl modem or cable modem but it's really been difficult for me to share this little modem to other computers. Right now I have my laptop connected to a hub, both computers are in the same workgroup and I have "share this computer internet to other computers"... etc. Problem is, I don't know what is currently happening... I'm hoping someone would guide me, I have googled and some people have been successful at sharing the connection but it seems I'm missing something =/ Let me know if you need any details, thanks

  Read the article

• Windows 2008 R2 server cannot access shares on other servers

  - by Rob

  I have a problem on my new 2008 R2 64-bit server. Essentially the server sometimes refuses to access shares on other server. in the format \\servernam\sharename sometime it works and then for a few hours it doesn't and then at randon it comes back online. This is a local AD network and have even put in a new gigabit switch between all server. All the old 2003 servers work fine so I know DNS and WINS is all ok. I get error 1006 in eventlog saying that my R2 server can't contact the domain controller when it clearly can. Just to add to the config, it is running on a Dell PowerEdge R410, Vmware Esxi 4.0 and R2 is configured as a terminal server. I can always view shares with FQDN This morning net view \\ did not work but net view \\ did. Very random and very frustrating. any ideas? thanks

  Read the article

• How to connect to a Virtualbox guest from the host when network cable unplugged

  - by Greg K

  I'd like to work offline (I'm flying to the US twice this month), to do this I need access to a linux development server. When I work from home I boot a VirtualBox VM and that acts as my dev server for the day (providing Apache, PHP & MySQL to run my server side code). However, I'd like to work with my VM when I'm not connected to a network. I have my Ubuntu VM guest set up with a bridge connection so it can serve HTTP and provide SSH access from inside my local network. I've tried to manually configure my network settings on both Mac OSX (the host) and Ubuntu (the guest) but I can't even ping my own NIC address (127.0.0.1 can, 192.168.21.x I can't) in OS X when I unplug the cable. Manual network settings: $ ifconfig en0 en0: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500 ether 00:xx:xx:xx:xx:xx inet 192.168.21.5 netmask 0xffffff00 broadcast 192.168.21.255 media: autoselect (100baseTX <full-duplex,flow-control>) status: active I can ping localhost fine, as well as my VM (.20) and SSH too. $ ping 192.168.21.5 PING 192.168.21.5 (192.168.21.5): 56 data bytes 64 bytes from 192.168.21.5: icmp_seq=0 ttl=64 time=0.085 ms 64 bytes from 192.168.21.5: icmp_seq=1 ttl=64 time=0.102 ms 64 bytes from 192.168.21.5: icmp_seq=2 ttl=64 time=0.100 ms 64 bytes from 192.168.21.5: icmp_seq=3 ttl=64 time=0.094 ms $ ping 192.168.21.20 PING 192.168.21.20 (192.168.21.20): 56 data bytes 64 bytes from 192.168.21.20: icmp_seq=0 ttl=64 time=0.910 ms 64 bytes from 192.168.21.20: icmp_seq=1 ttl=64 time=1.181 ms 64 bytes from 192.168.21.20: icmp_seq=2 ttl=64 time=1.159 ms 64 bytes from 192.168.21.20: icmp_seq=3 ttl=64 time=1.320 ms Network cable unplugged: $ ifconfig en0 en0: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500 ether 00:xx:xx:xx:xx:xx media: autoselect status: inactive $ ping 192.168.21.5 PING 192.168.21.5 (192.168.21.5): 56 data bytes ping: sendto: No route to host ping: sendto: No route to host Request timeout for icmp_seq 0 ping: sendto: No route to host Request timeout for icmp_seq 1 Does OS X disable the NIC when the network cable is unplugged? Any way to stop it doing this?

  Read the article

• Network Printers

  - by Jack

  We have a sever that shares all the printers. The PC's that are running on XP professional get a error message quoting (Connect to Printer). The only way I can find to get around the problem is by restating the printer and as soon is it comes online you can then add it but you have not got long. do you think it could be anything to-do with updates on the sever? the sever system is running Windows Server 2003 any help would be much appreciated. Thanks

  Read the article

• Finding cause of TCP retransmission within a LAN

  - by Surreal

  Hello denizens of Server Fault I have an irritating problem with a LAN of about 100 computers, 2 Windows domain servers, and 12 VoIP phones. Since their installation around a year ago, every week or so, we notice a VoIP phone resetting itself - occasionally in the middle of a call. Simultaneously there are often signs of temporary loss of connection on computers: freezes in explorer while accessing network shares, errors in our administration software due to loss of connection to the database server. I have been doing some Wireshark monitoring on the connection between the VoIP PBX and the rest of the network. Wireshark picks up a clump of retransmitted TCP packets at the times when we record phone restarts. The Wireshark log shows about 2 clusters of retransmissions a day ranging from 5 packets to hundreds. Those in each cluster are mainly between the PBX and some set of the VoIP phones, but not always the same set. Often retransmissions at the same time are to phones connected to the same switch, but sometimes retransmissions occur together to phones at opposite ends of the network. There are usually some coincident retransmissions in passing TCP traffic, for example between client machines and the file servers. The spikes in retransmissions and phone resets do not correlate well with when the network is heavily loaded. They seem to occur slightly more during the day, but most in the evening, when traffic should be decreasing. They occur reasonably often late at night when most computers are turned off and traffic should be lowest. Do you have any ideas that might help diagnose the cause of problems like this? One thing I have not yet tried, but should have, is updating the firmware of all the switches.

  Read the article

< Previous Page | 162 163 164 165 166 167 168 169 170 171 172 173  | Next Page >