Category: Chinese Post (中文帖子)

Posted on

[步骤] Linux 提高触发 Kdump 的几率

注意：

在提高触发 Kdump 的几率之前要先开启 Kdump：

Linux Kdump 的开启
（用于收集内核崩溃时的信息）

正文：

步骤一：配置提高触发 Kdump 几率的参数

1.1 配置提高触发 Kdump 几率的参数

# vim /etc/sysctl.conf

添加以下内容：

......
kernel.softlockup_panic = 1

1.2 让刚刚配置的参数生效

# sysctl -p

（注意：此时每有一次软锁都会触发 Kdump）

步骤二：当 Kdmup 触发后分析奔溃的信息

Linux Kdump 内核奔溃信息的分析

步骤三；删除提高触发 Kdump 几率的参数 （重要）

3.1 删除提高触发 Kdump 几率的参数 （重要）

# vim /etc/sysctl.conf

删除以下内容：

......
kernel.softlockup_panic = 1

3.2 让刚刚删除参数的配置生效 （重要）

# sysctl -p

（注意：此时每有一次软锁都会触发 Kdump）

参考文献：

https://www.suse.com/support/kb/doc/?id=000019217

Posted on

[工具] Shell 监控普通登录记录 （排除 SFTP 登录记录只监控普通登录记录）

注意：

在排除 SFTP 登录记录只监控普通登录记录前要先开启 SFTP 日志：

SFTP 日志的开启

正文：

介绍

基本信息

作者：朱明宇
名称：监控普通登录记录 （排除 SFTP 登录记录只监控普通登录记录）
作用：监控普通登录记录 （排除 SFTP 登录记录只监控普通登录记录）

使用方法

1. 在此脚本的分割线内写入相应的内容
2. 给此脚本添加执行权限
3. 执行此脚本
4. 普通登录记录会同时记录在系统日志和 $logfile 里

脚本分割线里的变量

1. logfile=logfile.txt #用户保存记录的文件
2. prompt=”and no sftp info” #记录里普通登录记录的文件

脚本

#!/bin/bash

####################### Separator ########################

logfile=logfile.txt
prompt="and no sftp info"

####################### Separator ########################

checktime=`date +%Y-%m-%dT%H -d "-1 day"`

for i in `cat -n /var/log/messages | grep $check_time | grep 'Started Session' | grep -v 'root' | awk '{print $1}'`

do
   line=`sed -n $[i]p /var/log/messages`
   time=`echo $line | awk '{print $1}'`
   session=`echo $line | awk '{print $6}'`
   user=`echo $line | awk '{print $9}'`
   user=${user%.}

   message="ACCESS CHECK LOG: Time:$time Session:$session $user has accessed `hostname`, $prompt"

   let sftpline=i+3

   sed -n $[sftpline]p /var/log/messages | grep sftp-server &> /dev/null
   if [ $? -ne 0 ];then
           echo $message
           echo $message >> $logfile.txt
           logger $message
   fi
   echo
done
Posted on

[命令] Linux 目标网站 SSL 证书的显示 （OpenSSL 版）

内容一：查看完整信息

# openssl s_client -connect eternalcenter.com:443
CONNECTED(00000003)
depth=2 C = US, O = Internet Security Research Group, CN = ISRG Root X1
verify return:1
depth=1 C = US, O = Let's Encrypt, CN = R3
verify return:1
depth=0 CN = eternalcenter.com
verify return:1
---
Certificate chain
 0 s:CN = eternalcenter.com
   i:C = US, O = Let's Encrypt, CN = R3
 1 s:C = US, O = Let's Encrypt, CN = R3
   i:C = US, O = Internet Security Research Group, CN = ISRG Root X1
 2 s:C = US, O = Internet Security Research Group, CN = ISRG Root X1
   i:O = Digital Signature Trust Co., CN = DST Root CA X3
---
Server certificate
-----BEGIN CERTIFICATE-----
MIIFKjCCBBKgAwIBAgISAxDxly99eBiarmHggFEmDJoMMA0GCSqGSIb3DQEBCwUA
MDIxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQswCQYDVQQD
EwJSMzAeFw0yMTEyMTkxMzA4MzJaFw0yMjAzMTkxMzA4MzFaMBwxGjAYBgNVBAMT
EWV0ZXJuYWxjZW50ZXIuY29tMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKC
AQEAtCcCuOqBrWP4eo//VBEXh668EjwrE1eXz2CS4GIN4ddn0rS8LHGFOrB92R8E
OnaYeTKpZjzNM3NA/AG/Gq5mTRZGTpyTasHEb/phwXdhrtJWdbMtQjGFSg8rXSB8
cap5NGP/NxAy8FV0MbXftg5t9VgBoCMGUzioSHZTEjefq+/OZwlP7RzxZN3bwj1D
61gWSw6q1X3bsi8ttwbkkiJfvjXo2KIeGOAnY10X+FPJmVa7jonhOuljrX4CYgnd
SCxmsfgwGMUzRu27VB1rEbKqvSr6tb9KfwFiqsZd5tTi7RW6WMqA0VbDV7BbDqLP
OzcturwRtXfzHjJxssy9zhnrQQIDAQABo4ICTjCCAkowDgYDVR0PAQH/BAQDAgWg
MB0GA1UdJQQWMBQGCCsGAQUFBwMBBggrBgEFBQcDAjAMBgNVHRMBAf8EAjAAMB0G
A1UdDgQWBBQMGBCfBuZxTAS8VcBI/13ugqc2RDAfBgNVHSMEGDAWgBQULrMXt1hW
y65QCUDmH6+dixTCxjBVBggrBgEFBQcBAQRJMEcwIQYIKwYBBQUHMAGGFWh0dHA6
Ly9yMy5vLmxlbmNyLm9yZzAiBggrBgEFBQcwAoYWaHR0cDovL3IzLmkubGVuY3Iu
b3JnLzAcBgNVHREEFTATghFldGVybmFsY2VudGVyLmNvbTBMBgNVHSAERTBDMAgG
BmeBDAECATA3BgsrBgEEAYLfEwEBATAoMCYGCCsGAQUFBwIBFhpodHRwOi8vY3Bz
LmxldHNlbmNyeXB0Lm9yZzCCAQYGCisGAQQB1nkCBAIEgfcEgfQA8gB3AN+lXqto
gk8fbK3uuF9OPlrqzaISpGpejjsSwCBEXCpzAAABfdMFzUsAAAQDAEgwRgIhAMFF
1orPZPnpCyhzwX2xZAZjJnOmDGmBjAl0tHnX4nEWAiEAqZTUwjrdwZAL+kDAgpzG
Me2RnGMseDBY8Oy2sefUgsAAdwBGpVXrdfqRIDC1oolp9PN9ESxBdL79SbiFq/L8
cP5tRwAAAX3TBc1zAAAEAwBIMEYCIQDLhR0nbVHEIL1uw9hRuv/ZbFjf91W/M4Jp
od7NTMQZbAIhAKEAAfmdu0nVHklyS2At1VValwQ6vNbqd0NQ85giG606MA0GCSqG
SIb3DQEBCwUAA4IBAQB/s+rZEaNrlUyBVnbxv5X9NTBd8buBOkR1qVswlS1R2i8B
pRjeJmgbiMzM2z5Mvx0yTIiCyXXUc3YaqoyxvddaQam9nlLGr0nKX9T5DkE7y0Fh
Qg0/ievRQF86XnDqQBxDR32jj5A1nKEiJrNCqugCWTAABndW3tvzK5DOsF2BfjJC
mcjwiKaSCjFVpf+KzLWS3UEW+DRTKOLBucXpenS7QEcQu4K6ShNSL7+K6UOZEbFu
uCRjOawCJFF7EH5vzRBy696Fu4EmzCV+c4rV8K8EcuCCQQeOTWJ/93Jv6U6kGrmE
P6wlcHFy1tZhTAmXf/qcpE3sGeH58OlNNiVmNJdH
-----END CERTIFICATE-----
subject=CN = eternalcenter.com

issuer=C = US, O = Let's Encrypt, CN = R3

---
No client certificate CA names sent
Peer signing digest: SHA256
Peer signature type: RSA-PSS
Server Temp Key: X25519, 253 bits
---
SSL handshake has read 4695 bytes and written 412 bytes
Verification: OK
---
New, TLSv1.2, Cipher is ECDHE-RSA-AES256-GCM-SHA384
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
SSL-Session:
    Protocol  : TLSv1.2
    Cipher    : ECDHE-RSA-AES256-GCM-SHA384
    Session-ID: D63BC88824810A4D43ACE901AD4FF2D82073BC6F0D8B2DE71F6310CA1C87707F
    Session-ID-ctx: 
    Master-Key: A6836430C394B96DDD5552867D49802F94AAC8BF5E882100F0D27185CF5CFD6A946B94D87652E44A6684FC9781D16D90
    PSK identity: None
    PSK identity hint: None
    SRP username: None
    TLS session ticket lifetime hint: 300 (seconds)
    TLS session ticket:
    0000 - bb be 55 e0 4b 6d c3 08-cd bc 45 6e 79 67 fc eb   ..U.Km....Enyg..
    0010 - 30 d5 4c 8a 5a c8 f7 13-42 4b 1d 02 ce 94 c0 b8   0.L.Z...BK......
    0020 - d7 cf f6 f0 ee 9d 49 5b-0a c8 a4 1a 8b dd 8a e0   ......I[........
    0030 - 66 83 52 9b 31 4d da 9e-d5 05 1a 70 ca e9 86 5e   f.R.1M.....p...^
    0040 - f5 09 a1 1c 92 6b 64 90-b7 e1 0e ec 30 e2 26 68   .....kd.....0.&h
    0050 - 49 13 10 9e 3e a5 e0 13-a2 f1 7a 7c c5 ad 99 6c   I...>.....z|...l
    0060 - e9 f6 1d 46 5f cc f6 f9-c5 f6 05 49 53 78 7e ea   ...F_......ISx~.
    0070 - 8c 17 eb 8d 96 c3 3f 92-fe e0 f0 f6 86 59 05 c8   ......?......Y..
    0080 - d2 8c 27 6b 9d 65 38 20-84 d4 23 54 35 70 19 4d   ..'k.e8 ..#T5p.M
    0090 - db 35 6d f4 44 50 d7 6e-a5 87 2b 32 e5 f8 42 88   .5m.DP.n..+2..B.
    00a0 - 28 e2 ab 35 e1 2c 06 71-e5 b2 82 cb 3a 75 cc 72   (..5.,.q....:u.r
    00b0 - ed ae e1 12 ff 82 6c 3a-3a 38 7a 8c 3c 9c f1 10   ......l::8z.<...
    00c0 - 78 b8 37 87 c3 a2 00 76-01 72 8c ef 3b 20 48 28   x.7....v.r..; H(

    Start Time: 1644931899
    Timeout   : 7200 (sec)
    Verify return code: 0 (ok)
    Extended master secret: yes
---
closed

（补充：这里以显示 eternalcenter.com 的 443 端口的 SSL 证书为例）

内容二：查看主要信息

# echo | openssl s_client -connect scc.suse.com:443 | head -n 16
CONNECTED(00000003)
depth=2 C = US, O = Internet Security Research Group, CN = ISRG Root X1
verify return:1
depth=1 C = US, O = Let's Encrypt, CN = R3
verify return:1
depth=0 CN = eternalcenter.com
verify return:1
---
Certificate chain
 0 s:CN = eternalcenter.com
   i:C = US, O = Let's Encrypt, CN = R3
 1 s:C = US, O = Let's Encrypt, CN = R3
   i:C = US, O = Internet Security Research Group, CN = ISRG Root X1
 2 s:C = US, O = Internet Security Research Group, CN = ISRG Root X1
   i:O = Digital Signature Trust Co., CN = DST Root CA X3
---

（补充：这里以显示 eternalcenter.com 的 443 端口的 SSL 证书为例）

Posted on

[步骤] SUSE Repository Mirroring Tool (RMT) 客户端的注册和取消注册

正文：

步骤一：注册客户端到 SUSE Repository Mirroring Tool (RMT)

1.1 通过使用 SUSEConnect 命令注册

如果是 HTTP 协议：

# SUSEConnect --url http://<SUSE Repository Mirroring Tool (RMT) Server's IP address or FQDN>

或者：

# SUSEConnect --url http://<SUSE Repository Mirroring Tool (RMT) Server's IP address or FQDN>:80

如果是 HTTPS 协议：

# SUSEConnect --url https://<SUSE Repository Mirroring Tool (RMT) Server's IP address or FQDN>

或者：

# SUSEConnect --url http://<SUSE Repository Mirroring Tool (RMT) Server's IP address or FQDN>:443

1.2 通过 RMT server 的脚本注册

1.2.1 从 RMT 服务器下载 rmt-client-setup 脚本

如果是 HTTP 协议：

# curl http://<SUSE Repository Mirroring Tool (RMT) Server's IP address or FQDN>/tools/rmt-client-setup --output rmt-client-setup

如果是 HTTPS 协议：

# curl https://<SUSE Repository Mirroring Tool (RMT) Server's IP address or FQDN>/tools/rmt-client-setup --output rmt-client-setup
1.2.2 执行 rmt-client-setup 脚本

如果是 HTTP 协议：

# sh rmt-client-setup http://RMT_SERVER/

如果是 HTTPS 协议：

# sh rmt-client-setup https://RMT_SERVER/

步骤二：查看客户端到 SUSE Repository Mirroring Tool (RMT) 的注册状态

# SUSEConnect --status-text

步骤三：取消注册客户端到 SUSE Repository Mirroring Tool (RMT)

3.1 取消注册客户端到 SUSE Repository Mirroring Tool (RMT)

# SUSEConnect –de-register

或者：

# SUSEConnect -d

3.2 清空客户端与 SUSE Repository Mirroring Tool (RMT) 相关的缓存

# SUSEConnect --cleanup

3.3 删除客户端与 SUSE Repository Mirroring Tool (RMT) 相关的文件

# rm -f /etc/SUSEConnect
# rm -rf /etc/zypp/credentials.d/*
# rm -rf /etc/zypp/repos.d/*
# rm -f /etc/zypp/services.d/*

参考文献：

https://documentation.suse.com/sles/15-SP1/single-html/SLES-rmt/index.html#sec-rmt-client-clientsetupscript