Change the current timezone in CentOS 6 and older Type the following commands as root: cp /etc/localtime /root/old.timezone rm /etc/localtime ln -s /usr/share/zoneinfo/America/Chicago /etc/localtime
The solution is to add the following line to ~/.ssh/config on every client machine (every machine where you run the SSH client): PubkeyAcceptedKeyTypes=+ssh-dss If the server is using OpenSSH 7.0 or newer, you’ll also need to add this line to /etc/ssh/sshd_config on each server machine.
So, after some digging, I just found a quick (but temporary) solution: Just comment out the setting of “jdk.jar.disabledAlgorithms” in the file of”lib/security/java.security” (which is located at “/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/lib/security/java.security, on my MacOS 10.12) # jdk.jar.disabledAlgorithms=MD2, MD5, RSA keySize < 1024 After that, the JNLP file will be running as usual again.
To understand how ARP translates IP addresses to MAC addresses, consider the following example. Assume host A has an IP address of 192.0.2.5/24 and a MAC address of fc:99:47:49:d4:a0, and wants to send a packet to host B with an IP address of 192.0.2.7. Note that the network number is the same for both hosts, so host A is able to send frames directly… Continue reading How Arp works in Linux
To understand how VLANs work, let’s consider VLAN applications in a traditional IT environment, where physical hosts are attached to a physical switch, and no virtualization is involved. Imagine a scenario where you want three isolated networks but you only have a single physical switch. The network administrator would choose three VLAN IDs, for example,… Continue reading How Vlan works in plain language
SR、LRM、LR、ER、ZR are terms used in fiber optic communications, stand for the transmission distance of the 10G modules. SR stands for Short Range, these transceivers support link length of 300m over multi-mode fiber and use 850nm lasers. LRM means Long Reach Multimode, these transceivers support distance up to 220m over multi-mode fiber and use 1310nm lasers.… Continue reading The meanings of SR、LRM、LR、ER and ZR
Many people think that docker is a kind of monolithic system and they hardly understand how internally it works. see the figure below
check the driver lists and set https://docs.openstack.org/kilo/config-reference/content/list-of-compute-config-options.html