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

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SSH port forwarding

SSH port forwarding is a mechanism in SSH for tunneling application ports from the client machine to the server machine, or vice versa.

Suppose we wish to visit a port in remote but behind the firewall, we can use SSH port forwarding to bind that port into local.

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Linux 手动安装字体

一般情况下, 我们有很多工具可以安装字体, 即便在 linux 下, Gnome 等也提供了很多工具来这么做.

不过有时候会有些特殊需求. 比如我们要在某个远程服务器上添加一个字体.

有一些简单的方法可以处理. (more…)

fstab 文件格式检查

我们通常编辑 /etc/fstab 来确定启动时候挂载的硬盘, swap 等. 若文件内容有误, 重启后的效果就是直接挂了, 然后必须通过安全模式或者单用户模式进去修改, 这很麻烦.

可否不重启就检查下 fstab 呢? 答案是可以的. (more…)

如何rsync同步非标准SSH接口

一般情况下,我们用rsync可以很容易的同步一个远程目录.

$ rsync -avzh --progress --delete \
    name@remote_host:source_dir target_dir

这样就把远程的一个目录同步回来了.

但是现在问题来了,当 port 为非标准的 22 端口时, 我们应该怎样加参数呢?比如有时候我们会 NAT 到 2222 端口.

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