For my case, I need to bypass one intermediate server so that I can connect to the remote server with vnc. For example, there are two servers (s1, s2) except my local PC and I have to login to s1 so that I can login s2 from my local PC. However, now, I need to
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Tag: Network
How to add two static IPs for a Xen VM?
Posted onHello, I have installed Xen4Centos on Centos7, having single NIC card with bridge network and have two VMs on that. In one VM, I want to add two static IP one for webserver and one for mail server. So I have created IP alias in guest VM, it was created but it was not pinging
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Allowing root Access to NFS Directories
Posted onFor local filesystems, root usually has full access (read/write) to directories/files inside of it. But for NFS directory mounted from network, root usually has no permission to write to directories or files within the NFS directory. How to make root act similarly in an NFS directory to the behavior in local directories? The reason that
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how to use pc internet of window8 on iphone 4s via usb
Posted onhow to use pc internet on iPhone 4s wia usb cable, pc is of window 8 and in network setting its not showing of connection of I phones network I ever wrote a tutorial at http://www.systutorials.com/136003/iphone-connecting-internet-using-windows-pc-network-through-usb-cable/ . But please be aware that it worked only on specific OS combinations. So, I am not sure whether
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Which ssh client on iOS works the best for socks?
Posted onThere are good ssh clients on Windows and, needless to mention, Linux. But which ssh client on iOS for iPhone/iPad works the best for socks? You may try vSSH. It is the best SSH client app I found on iOS. vSSH supports tunneling/port forwarding: you can setup port tunneling in the “Port forwarding” section of
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How to configure ifcfg-eth0 network scripts on Fedora/RHEL Linux?
Posted onHow to configure the ifcfg-* network script files under /etc/sysconfig/network-script/ on Fedora/RHEL Linux? Following is a very typical ifcfg-eth0 file setting static IP/gateway/network mask: DEVICE=eth0 BOOTPROTO=none ONBOOT=yes NETMASK=255.255.0.0 IPADDR=192.168.1.151 GATEWAY=192.168.1.10 USERCTL=no More options are supported, here you can find a reference: Interface Configuration Files (a easier to read PDF from F15 doc).
How to advertise different gateway ip via DHCP in OpenWRT?
Posted onHow to advertise a different router/gateway ip via DHCP in OpenWRT? In general, you need to configure the DHCP option with code 3 (router). (A list of all options can be found in http://www.networksorcery.com/enp/protocol/bootp/options.htm ) For example, to advise the gateway IP 192.168.1.2, you will send this option: “3,192.168.1.2” Now, for OpenWRT, you have 2
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How to find out the MX record for a domain on Linux?
Posted onHow to find out a domain’s MX record for Email on Linux? For example, to find which domain/IP the email to gmail.com is delivered to. You may make use of the host command. The -t option is used to select the query type. type can be any recognized query type: CNAME, NS, SOA, SIG, KEY,
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How to force umount a NFS directory on Linux?
Posted onThe NFS server is down. It is reported “Stale NFS file handle”. I tried ‘umount’ and ‘umount -f’. But neither succeeded. # umount /mnt/store umount.nfs: /mnt/store: Stale NFS file handle # umount -f /mnt/store umount.nfs: /mnt/store: Stale NFS file handle How to force umounting the NFS without rebooting the Linux server? I usually have to
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How to enable SSH service on Fedora Linux?
Posted onHow to enable SSH service on Fedora Linux? By default, it seems ssh is not enabled. Fedora may not have sshd service installed/enabled by default. You will need to install and configure it by yourself. The following instructions is for Fedora 22 as an example. First, install the sshd server by # dnf install openssh-server
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How to make curl request pass the Squid proxy?
Posted onI use curl to send requests to remote servers like following command. curl http://example.com/send –date-urlencode “data=hello” However, it is blocked by the network proxy squid in some networks with message like (some info anonymized with “…”): ERROR The requested URL could not be retrieved POST /… HTTP/1.1 Proxy-Authorization: Basic … User-Agent: Mozilla/4.0 (compatible;) Host: …
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How to find a network adapter’s speed in Linux?
Posted onI have a Linux box and it is connected to a network through a network adapter, say gate. How to find what is the current speed (10Mbps, 100Mbps or 1000Mbps) of the adapter? You can find the network adapter speed by the ethtool command: ethtool: query or control network driver and hardware settings For example,
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How to find a wireless network adapter’s speed in Linux?
Posted onHow to find a wireless adapter‘s speed in Linux? ethtool does not show the speed of the wireless adapters. For finding the configured speed of wireless adpaters in Linux, you can use the iwconfig tool. iwconfig: configure a wireless network interface For example, to find the speed of the wireless adapter wlp8s0: # iwconfig wlp8s0
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rtnetlink answers file exists
Posted onWhen you replace dynamic IP to static IP, you may need to restart your netwrok on Debian as follows. $sudo /etc/init.d/networking restart … …. reconfiguring network interfaces…rtnetlink answers file exists … However, error happens here “rtnetlink answers file exists”. How to solve it??? Run following commands could solve this problem # ip addr flush dev
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How to find which program or process is listening on a certain port in Linux?
Posted onMy program reports that the port is already used. How to find which program or process is listening on a certain port in Linux? You can use netstat to do this. netstat can print network connections. For example, to find which program is listing on port 9999 netstat -pln | grep 9999 You will need
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How to limit the network rate used by scp in Linux?
Posted onI am using a shared network and scp to upload files. I do not want to use most of the bandwidth available. How to limit the network rate used by scp in Linux? You can use the -l option of scp to limit the rate of bandwidth. -l limit Limits the used bandwidth, specified in
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How to use OpenVPN together with Ovpn Spider on iPhone?
Posted onBut.. how to use the OpenVPN together with Ovpn Spider on iPhone? You can check OpenVPN + Ovpn Spider: Free VPNs for iPhone Users.
How to configure interface bonding in Linux?
Posted onHow to configure interface bonding to bound to 2 eth interfaces together in Linux, specifically CentOS/RHEL? This tutorial Configuring Interface Bonding on CentOS/RHEL/OEL 6.x introduces setting up interface bonding well on CentOS / RHEL / OEL 6.
How to resolve a domain name from a specific DNS server instead of the configured one in Linux?
Posted onI would like to check whether the domain name’s IP has changed in the authoritative DNS server. The system’s configured DNS server may still cache the old IP, which is fine. The question is how to query from the authoritative DNS server the new IP? You can use dig – DNS lookup utility to query
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How to use iPhone to browse blocked websites in mainland China?
Posted onHow to use iPhone to browse blocked websites in mainland China? FYI: on iPhone, these 2 Apps are the favorite combination I am using for visiting blocked websites in mainland China: Check OpenVPN + Ovpn Spider: Free VPNs for iPhone Users for how to use them together. OpenVPN is for setting up OpenVPN VPN connection.
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