zfs cache file regenerate

The /etc/zfs/zpool.cache file Whenever a pool is imported on the system it will be added to the /etc/zfs/zpool.cache file. This file stores pool configuration information, such as the device names and pool state. If this file exists when running the zpool import command then it will be used to determine the list of pools available for import. When… Continue reading zfs cache file regenerate

Openssh 7+ ssh-dsa error fixed

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.

Categorized as Big Data Tagged

How Arp works in Linux

  To understand how ARP translates IP addresses to MAC addresses, consider the following example. Assume host A has an IP address of 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 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

The meanings of SR、LRM、LR、ER and ZR

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

Problem with SSD corruption on power failure .. flactuation

only enterprise-class SSDs can be relied upon (at all) for safe behavior on power fail. The enterprise-class SSDs have super-capacitors that store enough power to write all data stored in the RAM within the SSD on power fail, and vendors charge three times as much as they do for consumer class SSDs. Some vendors do… Continue reading Problem with SSD corruption on power failure .. flactuation

how to check if you have open port gateway linux

you can use nmap to test open port gateway see below https://nmap.org/nsedoc/scripts/ip-forwarding.html or you can use nping as follows   # nping –icmp –dest-mac [gateway mac] [target ip] You can find your router’s mac in your local ARP cache: $ arp -v [gateway ip]  

linux gateway

sysctl -w net.ipv4.ip_forward=1 iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

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