Code

Avoid stuck after ‘SSH2_MSG_SERVICE_ACCEPT received’

It is becoming pretty slow in SSH to a CentOS server.

Trying to print a verbose log:

$ ssh -vvvv my-host
....
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey out after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug1: SSH2_MSG_NEWKEYS received
debug2: set_newkeys: mode 0
debug1: rekey in after 134217728 blocks
debug1: Will attempt key: /Users/user/.ssh/id_rsa RSA SHA256:XXXXX/gNY explicit
debug2: pubkey_prepare: done
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug3: receive packet: type 6
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug3: send packet: type 50
..... <<<-- long long long silence here
debug3: receive packet: type 51 <<<-- and then continue to access the server
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password
debug3: start over, passed a different list publickey,gssapi-keyex,gssapi-with-mic,password
debug3: preferred publickey,keyboard-interactive,password

(more…)

By Yu, ago

The short-circuiting in bash

Bash script writing is a import approach to configure the linux system. Suppose we wish to add a user if not exists, the command may seems as follow:

TARGET_USER=alice
if (! id -u $TARGET_USER > /dev/null 2>&1 ); then
    echo "creating user $TARGET_USER"
    # adduser $TARGET_USER
fi

However, it is kind of too long. In this case short-circuiting is a alternative solution. (more…)

By Yu, ago

A simple workflow to create a clean python library based on Anaconda

The open-source Anaconda Distribution is an easy way to perform Python/R data science and machine learning on Linux, Windows, and Mac OS X. We could easily prepare an isolated and constant environment on anywhere based on a configure file.

Considering the various kind of strange errors due to the different versions of python and python libraries, this management tool makes our life much more comfortable in deploying and cooperating.

(more…)

By Yu, ago