Category : Networking

Subnet to Mask Bits conversion table Mask CIDR Length (Mask Bits) 128.0.0.0 1 192.0.0.0 2 224.0.0.0 3 240.0.0.0 4 248.0.0.0 5 252.0.0.0 6 254.0.0.0 7 255.0.0.0 8 255.128.0.0 9 255.192.0.0 10 255.224.0.0 11 255.240.0.0 12 255.248.0.0 13 255.252.0.0 14 255.254.0.0 15 255.255.0.0 16 255.255.128.0 17 255.255.192.0 18 255.255.224.0 19 255.255.240.0 20 255.255.248.0 21 255.255.252.0 22 ..

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How to tell the network speed of network cards in Linux? CentOS 7 Find the network cards: ip addr 1: lo: mtu 65536 qdisc noqueue state UNKNOWN qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens160: mtu 1500 qdisc ..

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How do I display a list of all network cards under Linux operating systems? You can use any one of the following command to list network cards installed under Linux operating systems. Please note that the ifconfig and ip commands will also display interfaces information about vpn, loopback, and other configured interfaces. lspci command : ..

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The ‘neighbor table overflow’ is a VERY common linux issue on large networks. Some network trigger this with default linux settings (because the previous network regime put so many IP address subnets on a single vlan , it creates large ARP tables – which is not normal / default settings). It is not an indication ..

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Add the IP as Eth0 when the primary is Eth1 (no gateway) # nano /etc/network/interfaces auto lo iface lo inet loopback auto eth0 iface eth0 inet static address 10.168.19.36 netmask 255.255.255.224 hwaddress 0C:C4:7A:6A:0F:E4 auto eth1 iface eth1 inet static address 206.xxx.xx.xx netmask 255.255.255.0 gateway 206.xxx.xx.1 hwaddress 0C:C4:7A:6A:0F:E5 dns-nameservers 8.8.8..

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Server connections speeds are a function of a variety of variables. The server’s connection speed to the Internet, all processes that are simultaneously trying to connect (uploads and downloads share the total speed available), the overall health of the Internet and the connection capability of the off-site computer, which is also limited by the same ..

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Useful commands to check if a server is getting ddos’d Show IPs with more than 10 connections open: # netstat -nat | grep “:80” | awk -F: ‘{print $8}’ | sort | uniq -c | sort -n | awk ‘{ if ( $1 > 10) print $2 ; }’ Show # of connections open per ..

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