).
124 |
125 | Get information about the request type
126 |
127 | $ grpc_cli type localhost:50051 helloworld.HelloRequest
128 | helloworld.HelloRequest is the full name of the request type.
129 |
130 | output:
131 |
132 | message HelloRequest {
133 | optional string name = 1;
134 | }
135 | Call a remote method
136 | We can send RPCs to a server and get responses using grpc_cli call command.
137 |
138 | Call a unary method Send a rpc to a helloworld server at localhost:50051:
139 |
140 | $ grpc_cli call localhost:50051 SayHello "name: 'gRPC CLI'"
141 | output: sh message: "Hello gRPC CLI"
142 |
143 | SayHello is (part of) the gRPC method string. Then "name: 'world'" is the text format of the request proto message. For information on more flags, look at the comments of grpc_cli.cc.
144 |
145 | Use local proto files
146 |
147 | If the server does not have the server reflection service, you will need to provide local proto files containing the service definition. The tool will try to find request/response types from them.
148 |
149 | $ grpc_cli call localhost:50051 SayHello "name: 'world'" \
150 | --protofiles=examples/protos/helloworld.proto
151 | If the proto file is not under the current directory, you can use --proto_path to specify a new search root.
152 |
153 | Send non-proto rpc
154 |
155 | For using gRPC with protocols other than protobuf, you will need the exact method name string and a file containing the raw bytes to be sent on the wire.
156 |
157 | $ grpc_cli call localhost:50051 /helloworld.Greeter/SayHello \
158 | --input_binary_file=input.bin \
159 | --output_binary_file=output.bin
160 | On success, you will need to read or decode the response from the output.bin file.
--------------------------------------------------------------------------------
/Cluster/Kubernetes/Heptio/Ark:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/gofunct/devops/53b0c05f1af7957252ca2b84dd80c9dc676520fb/Cluster/Kubernetes/Heptio/Ark
--------------------------------------------------------------------------------
/Cluster/README.md:
--------------------------------------------------------------------------------
1 | # Coming Soon!
--------------------------------------------------------------------------------
/Language/Bash/README.md:
--------------------------------------------------------------------------------
1 | ### Date Handling
2 |
3 | #### Convert Date To Unix Timestamp
4 |
5 | show
6 |
7 |
8 | date -d "$date" +%s
9 |
10 | Note that this only works for American style dates. European
11 | "25.06.2014" like dates are not supported. The simple solution is to
12 | convert them first to "2014-06-25" for example with
13 |
14 | sed 's/\([0-9]*\)\.\([0-9]*\)\.([0-9]*\)/\3-\2-\1/'
15 |
16 |
17 | show
22 |
23 |
24 |
25 | date -d "1970-01-01 1234567890 sec GMT"
26 |
27 |
28 | show
33 |
34 |
35 |
36 | Found
37 | [here](http://delicious.com/redirect?url=http%3A//www.unix.com/shell-programming-scripting/21877-how-get-month-last-date-unix.html):
38 |
39 | cal $(date "+%M %y") | grep -v ^$ | tail -1 | sed 's/^.* \([0-9]*\)$/\1/'
40 |
41 |
42 | show
47 |
48 |
49 | Using "flock":
50 |
51 | flock /tmp/myapp.lock
52 | flock -w 10 /tmp/myapp.lock
53 |
54 | Using "lockfile-\*" commands:
55 |
56 | lockfile-create /tmp/myapp.lock
57 | lockfile-touch /tmp/myapp.lock
58 | lockfile-remove /tmp/myapp.lock
59 |
60 |
61 | show
68 |
69 |
70 | getopt is a standalone command, supporting GNU style long parameters and
71 | parameters mixed with options and can be used like this
72 |
73 | PARAMS=`getopt -o a::bc: --long arga::,argb,argc: -n 'myscript.sh' -- "$@"`
74 | eval set -- "$PARAMS"
75 |
76 | while true ; do
77 | case "$1" in
78 | -a|--arga)
79 | case "$2" in
80 | "") ARG_A='some default value' ; shift 2 ;;
81 | *) ARG_A=$2 ; shift 2 ;;
82 | esac ;;
83 | -b|--argb) ARG_B=1 ; shift ;;
84 | -c|--argc)
85 | case "$2" in
86 | "") shift 2 ;;
87 | *) ARG_C=$2 ; shift 2 ;;
88 | esac ;;
89 | --) shift ; break ;;
90 | *) echo "Unknown option!" ; exit 1 ;;
91 | esac
92 | done
93 |
94 |
95 | show
100 |
101 |
102 | getopts is shell-builtin
103 |
104 | while getopts ":ap:" opt; do
105 | case $opt in
106 | a)
107 | echo "Option -a ist set"
108 | ;;
109 | p)
110 | echo "Parameter -p is given with value '$OPTARG'"
111 | ;;
112 | \?)
113 | echo "Unknown option: -$OPTARG"
114 | ;;
115 | esac
116 | done
117 |
118 |
119 | show
124 |
125 |
126 | If you ever need to port between different Unix derivates use
127 | [shflags](https://code.google.com/p/shflags/) a Google library providing
128 | standard parameter handling. Example:
129 |
130 | source shflags
131 |
132 | DEFINE_string 'value' '0' 'an example value to pass with default value "0"' 'v'
133 |
134 | FLAGS "$@" || exit $?
135 | eval set -- "${FLAGS_ARGV}"
136 |
137 | echo "${FLAGS_value}!"
138 |
139 |
140 | show
145 |
146 |
147 | - [Shell Linting](https://github.com/koalaman/shellcheck)
148 | - [Mail Attachments](http://www.panix.com/%7Ekylet/unix-att.html):
149 | Dozens of variants to send mail attachments using Unix tools.
150 | - [tail -f until
151 | removed](http://lzone.de/follow+file+with+tail+until+removed): When
152 | you want to tail a file until it gets removed
153 |
154 | tail --follow=name myfile
155 |
156 | - [join - DB-like joining of CSV files](/how+to+join+CSV+Files):
157 |
158 | join -o1.2,2.3 -t ";" -1 1 -2 2 employee.csv tasks.csv
159 |
160 | (Note: works only on CSVs without quotes or multi-line strings)
161 |
162 | - [awk-based CSV
163 | Parser](https://github.com/geoffroy-aubry/awk-csv-parser)
164 | - list all commands:
165 |
166 | compgen -c |sort -u
167 |
168 | - Check for interactive terminal: Run "tty" in silent mode and check
169 | the exit code
170 |
171 | tty -s
172 |
173 | - [ANSI color matrix](/node/23)
174 | - Sorting column: Use the -k switch of "sort" to sort lines by a
175 | column. E.g.
176 |
177 | cat access.log | sort -k 1
178 |
179 | - [watch](http://www.commandlinefu.com/commands/tagged/583/watch):
180 | wait for file/directory changes and run a command
181 |
182 | watch -d ls -l
183 |
184 | - [Unbuffer
185 | Output](http://unix.stackexchange.com/questions/25372/turn-off-buffering-in-pipe):
186 |
187 | stdbuf -i0 -o0 -e0 # Best solution
188 |
189 | unbuffer # Wrapper script from expect
190 |
191 | - [Apply ulimit change in /etc/security/limits.conf
192 | immediately](/apply+limits+immediately)
193 | - [ulimit check list](/Debian+Ubuntu+ulimit+Check+List)
194 | - [ulimit change Apache limits](/Ubuntu+Apache+and+ulimit)
195 | - [ulimit Nagios Check
196 | Plugin](/Nagios%20Check%20Plugin%20for%20nofile%20Limit)
197 | - dos2unix with vi:
198 |
199 | :%s/^V^M//g
200 |
201 | - Resolving any file path to absolute path
202 |
203 | readlink -e
204 |
205 | or use
206 |
207 | pwd -P
208 |
209 | - Timeouts in shell:
210 |
211 | timeout
212 |
213 | - Convert encodings (HTTP URI encoding, HTML entity encoding...)
214 |
215 | recode ascii..html
216 | recode html..ascii
217 |
218 |
219 | show
10 |
11 |
12 | ```go
13 |
14 | package cmd
15 |
16 | import (
17 | "fmt"
18 |
19 | "github.com/spf13/cobra"
20 | )
21 |
22 | func init() {
23 | rootCmd.AddCommand(versionCmd)
24 | }
25 |
26 | var versionCmd = &cobra.Command{
27 | Use: "version",
28 | Short: "Print the version number of Hugo",
29 | Long: `All software has versions. This is Hugo's`,
30 | Run: func(cmd *cobra.Command, args []string) {
31 | fmt.Println("Hugo Static Site Generator v0.9 -- HEAD")
32 | },
33 | }
34 |
35 | ```
36 |
37 |
38 | show
47 |
48 |
49 | ```
50 |
51 | rootCmd.PersistentFlags().BoolVarP(&Verbose, "verbose", "v", false, "verbose output")
52 |
53 | ```
54 |
55 |
56 | show
65 |
66 |
67 | ```go
68 | rootCmd.Flags().StringVarP(&Source, "source", "s", "", "Source directory to read from")
69 |
70 | ```
71 |
72 |
73 | show
82 |
83 |
84 | ```go
85 | command := cobra.Command{
86 | Use: "print [OPTIONS] [COMMANDS]",
87 | TraverseChildren: true,
88 | }
89 |
90 | ```
91 |
92 |
93 | show
102 |
103 |
104 | ```
105 | var author string
106 |
107 | func init() {
108 | rootCmd.PersistentFlags().StringVar(&author, "author", "YOUR NAME", "Author name for copyright attribution")
109 | viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author"))
110 | }
111 |
112 | ```
113 |
114 |
115 | show
124 |
125 |
126 | ```
127 | rootCmd.Flags().StringVarP(&Region, "region", "r", "", "AWS region (required)")
128 | rootCmd.MarkFlagRequired("region")
129 |
130 | ```
131 |
132 |
133 | show
144 |
145 |
146 | ```
147 | The following validators are built in:
148 |
149 | * NoArgs - the command will report an error if there are any positional args.
150 | * ArbitraryArgs - the command will accept any args.
151 | * OnlyValidArgs - the command will report an error if there are any positional args that are not in the ValidArgs field of Command.
152 | * MinimumNArgs(int) - the command will report an error if there are not at least N positional args.
153 | * MaximumNArgs(int) - the command will report an error if there are more than N positional args.
154 | * ExactArgs(int) - the command will report an error if there are not exactly N positional args.
155 | * RangeArgs(min, max) - the command will report an error if the number of args is not between the minimum and maximum number of expected args.
156 |
157 | ```
158 |
159 |
160 | show
167 |
168 |
169 | ```golang
170 | var cmd = &cobra.Command{
171 | Short: "hello",
172 | Args: func(cmd *cobra.Command, args []string) error {
173 | if len(args) < 1 {
174 | return errors.New("requires at least one arg")
175 | }
176 | if myapp.IsValidColor(args[0]) {
177 | return nil
178 | }
179 | return fmt.Errorf("invalid color specified: %s", args[0])
180 | },
181 | Run: func(cmd *cobra.Command, args []string) {
182 | fmt.Println("Hello, World!")
183 | },
184 | }
185 |
186 | ```
187 |
188 |
189 | show
198 |
199 |
200 | ```
201 | package main
202 |
203 | import (
204 | "fmt"
205 | "strings"
206 |
207 | "github.com/spf13/cobra"
208 | )
209 |
210 | func main() {
211 | var echoTimes int
212 |
213 | var cmdPrint = &cobra.Command{
214 | Use: "print [string to print]",
215 | Short: "Print anything to the screen",
216 | Long: `print is for printing anything back to the screen.
217 | For many years people have printed back to the screen.`,
218 | Args: cobra.MinimumNArgs(1),
219 | Run: func(cmd *cobra.Command, args []string) {
220 | fmt.Println("Print: " + strings.Join(args, " "))
221 | },
222 | }
223 |
224 | var cmdEcho = &cobra.Command{
225 | Use: "echo [string to echo]",
226 | Short: "Echo anything to the screen",
227 | Long: `echo is for echoing anything back.
228 | Echo works a lot like print, except it has a child command.`,
229 | Args: cobra.MinimumNArgs(1),
230 | Run: func(cmd *cobra.Command, args []string) {
231 | fmt.Println("Print: " + strings.Join(args, " "))
232 | },
233 | }
234 |
235 | var cmdTimes = &cobra.Command{
236 | Use: "times [# times] [string to echo]",
237 | Short: "Echo anything to the screen more times",
238 | Long: `echo things multiple times back to the user by providing
239 | a count and a string.`,
240 | Args: cobra.MinimumNArgs(1),
241 | Run: func(cmd *cobra.Command, args []string) {
242 | for i := 0; i < echoTimes; i++ {
243 | fmt.Println("Echo: " + strings.Join(args, " "))
244 | }
245 | },
246 | }
247 |
248 | cmdTimes.Flags().IntVarP(&echoTimes, "times", "t", 1, "times to echo the input")
249 |
250 | var rootCmd = &cobra.Command{Use: "app"}
251 | rootCmd.AddCommand(cmdPrint, cmdEcho)
252 | cmdEcho.AddCommand(cmdTimes)
253 | rootCmd.Execute()
254 | }
255 |
256 | ```
257 |
258 |
259 | show
8 |
9 |
10 | ### String
11 |
12 | ```
13 |
14 | ```
15 |
16 | ### Integer
17 |
18 | ```
19 |
20 | ```
21 |
22 | ### Floats
23 |
24 | ```
25 |
26 | ```
27 |
28 | ### Boolean
29 |
30 | ```
31 |
32 | ```
33 |
34 | ### Array
35 |
36 | ```
37 |
38 | ```
39 |
40 | ### Slice
41 |
42 | ```
43 |
44 | ```
45 |
46 | ### Map
47 |
48 | ```
49 |
50 | ```
51 |
52 | ### Struct
53 |
54 | ```
55 |
56 | ```
57 |
58 |
59 |
60 | show
65 |
66 |
67 | ### Function
68 |
69 | ```
70 |
71 | ```
72 |
73 | ### Method
74 |
75 | ```
76 |
77 | ```
78 |
79 | ### Interface
80 |
81 | ```
82 |
83 |
84 | ```
85 |
86 |
87 | show
92 |
93 |
94 | ### If
95 |
96 | ```
97 |
98 | ```
99 |
100 | ### for
101 |
102 | ```
103 |
104 | ```
105 |
106 | ### switch
107 |
108 | ```
109 |
110 | ```
111 |
112 |
113 | show
118 |
119 |
120 | ### Select
121 |
122 | ```
123 |
124 | ```
125 |
126 | ### Chanel
127 |
128 | ```
129 |
130 | ```
131 |
132 | ### Goroutine
133 |
134 | ```
135 |
136 | ```
137 |
138 | ### Worker Pools
139 |
140 | ```
141 |
142 | ```
143 |
144 |
145 |
146 | show
151 |
152 |
153 | ```
154 |
155 | ```
156 |
157 |
158 | show
163 |
164 |
165 |
166 |
167 |
168 | show
173 |
174 |
175 |
176 |
177 |
178 | show
183 |
184 |
185 |
186 |
187 |
188 | show
193 |
194 |
195 |
196 |
197 |
198 | show
6 |
7 |
8 |
9 | For a system administrator, having to perform security vulnerability analysis and software update on a daily basis can be a burden.
10 | To avoid downtime in production environment, it is common for system administrator to choose not to use the automatic update option provided by package manager and to perform update manually.
11 | This leads to the following problems.
12 | - System administrator will have to constantly watch out for any new vulnerabilities in NVD(National Vulnerability Database) or similar databases.
13 | - It might be impossible for the system administrator to monitor all the software if there are a large number of software installed in server.
14 | - It is expensive to perform analysis to determine the servers affected by new vulnerabilities. The possibility of overlooking a server or two during analysis is there.
15 |
16 |
17 | Vuls is a tool created to solve the problems listed above. It has the following characteristics.
18 | - Informs users of the vulnerabilities that are related to the system.
19 | - Informs users of the servers that are affected.
20 | - Vulnerability detection is done automatically to prevent any oversight.
21 | - Report is generated on regular basis using CRON or other methods. to manage vulnerability.
22 |
23 | 
24 |
25 |
26 | show
35 |
36 |
37 |
38 | [Supports major Linux/FreeBSD](https://vuls.io/docs/en/supported-os.html)
39 | - Alpine, Ubuntu, Debian, CentOS, Amazon Linux, RHEL, Oracle Linux, SUSE Enterprise Linux and Raspbian, FreeBSD
40 | - Cloud, on-premise, Docker
41 |
42 |
43 | show
48 |
49 |
50 |
51 | Vuls uses Multiple vulnerability databases
52 | - [NVD](https://nvd.nist.gov/)
53 | - [JVN(Japanese)](http://jvndb.jvn.jp/apis/myjvn/)
54 | - OVAL
55 | - [RedHat](https://www.redhat.com/security/data/oval/)
56 | - [Debian](https://www.debian.org/security/oval/)
57 | - [Ubuntu](https://people.canonical.com/~ubuntu-security/oval/)
58 | - [SUSE](http://ftp.suse.com/pub/projects/security/oval/)
59 | - [Oracle Linux](https://linux.oracle.com/security/oval/)
60 | - [Alpine-secdb](https://git.alpinelinux.org/cgit/alpine-secdb/)
61 | - [Red Hat Security Advisories](https://access.redhat.com/security/security-updates/)
62 | - [Debian Security Bug Tracker](https://security-tracker.debian.org/tracker/)
63 | - Commands(yum, zypper, pkg-audit)
64 | - RHSA/ALAS/ELSA/FreeBSD-SA
65 | - Changelog
66 |
67 |
68 | show
73 |
74 |
75 | [Fast Scan](https://vuls.io/docs/en/architecture-fast-scan.html)
76 | - Scan without root privilege, no dependencies
77 | - Almost no load on the scan target server
78 | - Offline mode scan with no internet access. (Red Hat, CentOS, OracleLinux, Ubuntu, Debian)
79 |
80 | [Fast Root Scan](https://vuls.io/docs/en/architecture-fast-root-scan.html)
81 | - Scan with root privilege
82 | - Almost no load on the scan target server
83 | - Detect processes affected by update using yum-ps (RedHat, CentOS, Oracle Linux and Amazon Linux)
84 | - Detect processes which updated before but not restarting yet using checkrestart of debian-goodies (Debian and Ubuntu)
85 | - Offline mode scan with no internet access. (RedHat, CentOS, OracleLinux, Ubuntu, Debian)
86 |
87 | [Deep Scan](https://vuls.io/docs/en/architecture-deep-scan.html)
88 | - Scan with root privilege
89 | - Parses the Changelog
90 | Changelog has a history of version changes. When a security issue is fixed, the relevant CVE ID is listed.
91 | By parsing the changelog and analysing the updates between the installed version of software on the server and the newest version of that software
92 | it's possible to create a list of all vulnerabilities that need to be fixed.
93 | - Sometimes load on the scan target server
94 |
95 |
96 | show
101 |
102 |
103 | [Remote Scan](https://vuls.io/docs/en/architecture-remote-scan.html)
104 | - User is required to only setup one machine that is connected to other target servers via SSH
105 |
106 | [Local Scan](https://vuls.io/docs/en/architecture-local-scan.html)
107 | - If you don't want the central Vuls server to connect to each server by SSH, you can use Vuls in the Local Scan mode.
108 |
109 |
110 | show
115 |
116 |
117 | - It is possible to acquire the state of the server by connecting via SSH and executing the command.
118 | - Vuls warns when the scan target server was updated the kernel etc. but not restarting it.
119 |
120 |
121 | show
126 |
127 |
128 | - Scan middleware, programming language libraries and framework for vulnerability
129 | - Support software registered in CPE
130 |
131 |
132 | show
137 |
138 |
139 | - Nondestructive testing
140 | - Pre-authorization is *NOT* necessary before scanning on AWS
141 | - Vuls works well with Continuous Integration since tests can be run every day. This allows you to find vulnerabilities very quickly.
142 | - Auto generation of configuration file template
143 | - Auto detection of servers set using CIDR, generate configuration file template
144 | - Email and Slack notification is possible (supports Japanese language)
145 | - Scan result is viewable on accessory software, TUI Viewer on terminal or Web UI ([VulsRepo](https://github.com/usiusi360/vulsrepo)).
146 |
147 |
148 | show
155 |
156 |
157 |
158 | - Vuls doesn't update the vulnerable packages.
159 |
160 |
161 | show
6 |
7 |
8 |
9 |
10 |
11 | show
16 |
17 |
18 |
19 |
20 |
21 | show
26 |
27 |
28 |
29 |
30 |
31 | show
36 |
37 |
38 |
39 |
40 |
41 | show
46 |
47 |
48 |
49 |
50 |
51 | show
56 |
57 |
58 |
59 |
60 |
61 | show
66 |
67 |
68 |
69 |
70 |
71 | show
76 |
77 |
78 |
79 |
80 |
81 | show
86 |
87 |
88 |
89 |
90 |
91 | show
96 |
97 |
98 |
99 |
100 |
101 | show
106 |
107 |
108 |
109 |
110 |
111 | show
116 |
117 |
118 |
119 |
120 |
121 | show
126 |
127 |
128 |
129 |
130 |
131 | show
136 |
137 |
138 |
139 |
140 |
141 | show
146 |
147 |
148 |
149 |
150 |
151 | show
156 |
157 |
158 |
159 |
160 |
161 | show
166 |
167 |
168 |
169 |
170 |
171 | show
176 |
177 |
178 |
179 |
180 |
181 | show
186 |
187 |
188 |
189 |
190 |
191 | show
11 |
12 |
13 |
14 | Git Grep will return a list of lines matching a pattern.
15 |
16 | Running:
17 | ```bash
18 | $ git grep aliases
19 | ```
20 | will show all the files containing the string *aliases*.
21 |
22 | 
23 |
24 | *Press `q` to quit.*
25 |
26 | You can also use multiple flags for more advanced search. For example:
27 |
28 | * `-e` The next parameter is the pattern (e.g., regex)
29 | * `--and`, `--or` and `--not` Combine multiple patterns.
30 |
31 | Use it like this:
32 | ```bash
33 | $ git grep -e pattern --and -e anotherpattern
34 | ```
35 |
36 | [*Read more about the Git `grep` command.*](http://git-scm.com/docs/git-grep)
37 |
38 |
39 | show
9 |
10 |
11 | openssl x509 -text -in my.pem
12 | openssl ca -text -in my_ca.pem
13 | openssl req -text -in csr.pem
14 |
15 |
16 | show
21 |
22 |
23 |
24 | openssl req -text -noout -verify -in csr.pem
25 | openssl rsa -in my.key -check
26 | openssl pkcs12 -info -in keystore.p12
27 |
28 |
29 | show
34 |
35 |
36 | openssl x509 -enddate -noout -in file.pem # prints something like 'notAfter=Nov 3 22:23:50 2014 GMT'
37 | openssl x509 -checkend 86400 -noout -in file.pem # gives exitcode 0 if not expired
38 |
39 |
40 | show
45 |
46 |
47 |
48 | openssl s_client -connect example.com:443
49 |
50 | # With advanced TLS and OSCP debugging:
51 | openssl s_client -connect example.com:443 -tls1 -tlsextdebug -status
52 |
53 |
54 | show
59 |
60 |
61 | openssl version -a
62 |
63 |
64 | show
69 |
70 |
71 |
72 | c_rehash
73 |
74 |
75 | show
80 |
81 |
82 |
83 | Certificate: openssl x509 -noout -modulus -in server.crt | openssl md5
84 | Private Key: openssl rsa -noout -modulus -in server.key | openssl md5
85 | CSR: openssl req -noout -modulus -in server.csr | openssl md5
86 |
87 |
88 | show
93 |
94 |
95 | openssl rsa -in key-with-pwd.pem -out key-without-pwd.pem
96 |
97 |
98 | show
6 |
7 |
8 |
9 | ls -Z
10 |
11 |
12 | show
17 |
18 |
19 | getenforce
20 |
21 |
22 | show
27 |
28 |
29 |
30 | echo 0 >/selinux/enforce
31 |
32 | # or
33 |
34 | setenforce 0
35 |
36 |
37 | show
42 |
43 |
44 |
45 | selinux=0
46 |
47 |
48 | show
53 |
54 |
55 | SELINUX=disabled
56 | SELINUXTYPE=targeted
57 | SETLOCALDEFS=0
58 |
59 |
60 | show
65 |
66 |
67 | apt-get install selinux-basics selinux-policy-default auditd
68 | selinux-activate
69 | # Reboot
70 | check-selinux-installation
71 |
72 |
73 | show
78 |
79 |
80 |
81 | sestatus
82 | getenforce
83 |
84 |
85 | show
90 |
91 |
92 | semodule -i my_module.pp
93 |
94 |
95 | show
4 |
5 |
6 | /abc/p # Print all with "abc"
7 | /abc/!p # Print all without "abc"
8 | /abc/d # Delete all with "abc"
9 | /abc/!d # Delete all without "abc"
10 |
11 | /start/,/end/!d # Select a block
12 |
13 | s/abc/def/
14 | s/abc\(...\)ghi/\1/ # Back references
15 | # (see below for correct Shell quoting)
16 |
17 | /abc/{s/def/ghi)} # Conditional replace
18 |
19 |
20 | show
27 |
28 |
29 | To edit file use the -i option this safely changes the file contents
30 | without any output redirection needed.
31 |
32 | sed -i 's/abc/ABC/' myfile.txt
33 | sed -i '/deleteme/d' *
34 |
35 |
36 | show
41 |
42 |
43 | Often grep and sed are used together. In all those cases grep can be
44 | dropped. For example
45 |
46 | grep "pattern" file | sed "s/abc/def/"
47 |
48 | can be written as
49 |
50 | sed -n "/pattern/p; s/abc/def/"
51 |
52 |
53 | show
58 |
59 |
60 | Always use single quotes!
61 |
62 | sed 's/^.*\(pattern\).*/\1/'
63 |
64 |
65 | show
70 |
71 |
72 |
73 | If you want to do extraction and need a pattern based on single quotes
74 | use \\x27 instead of trying to insert a single quote. For example:
75 |
76 | sed 's/.*var=\x27\([^\x27]*\)\x27.*/\1/'
77 |
78 | to extract "some string" from "var='some string'". Or if you don't know
79 | about the quoting, but know there are quotes
80 |
81 | sed 's/.*var=.\([^"\x27]*\)..*/\1/'
82 |
83 |
84 | show
89 |
90 |
91 | sed '/conditional pattern/{s/pattern/replacement/g}'
92 |
93 | #### Prefix files with a boilerplate using sed
94 |
95 | sed -i '1s/^/# DO NOT TOUCH THIS FILE!\n\n/' *
96 |
97 |
98 | show
103 |
104 |
105 | The only way to remove new line is this:
106 |
107 | sed ':a;N;$!ba;s/\n//g' file
108 |
109 | Check out [this explanation](/Removing-newlines-with-sed) if you want to
110 | know why.
111 |
112 |
113 | show
118 |
119 |
120 | sed '/first line/,/last line/!d' file
121 |
122 |
123 | show
28 |
29 |
30 | systemctl edit
31 | systemctl daemon-reload # after directly modifying/adding config files
32 |
33 | Global definitions from /lib/systemd/system will then be overruled by a
34 | new file in /etc/systemd/system
35 |
36 |
37 | show
42 |
43 |
44 |
45 | systemctl stop
46 | systemctl disable
47 | rm /etc/systemd/system/
48 | systemctl daemon-reload
49 | systemctl reset-failed
50 |
51 |
52 | show
57 |
58 |
59 |
60 | To help identify cgroup/process relations run
61 |
62 | ps xawf -eo pid,user,cgroup,args
63 |
64 | or
65 |
66 | systemd-cgls
67 |
68 |
69 | show
74 |
75 |
76 |
77 | Print startup time per service
78 |
79 | systemd-analyze blame
80 |
81 |
82 | show
87 |
88 |
89 |
90 | Log directory is /var/log/journal
91 |
92 | journalctl # Print all log entries
93 | journalctl -b # Print everything since boot
94 | journalctl -e # Print last page of the journal
95 | journalctl -f # Print last 10 entries and continues (like tail -f)
96 | journalctl -u # Print for unit only
97 | journalctl --no-pager # Non-interactive mode
98 |
99 | journalctl --vacuum-size=100M # Remove logs until <100MB is used
100 | journalctl --vacuum-time=2weeks # Remove logs older 2 weeks
101 |
102 |
103 | show
108 |
109 |
110 |
111 | hostnamectl
112 | timedatectl
113 | localctl
114 | loginctl
115 |
116 | systemd-detect-virt
117 |
118 |
119 | show
124 |
125 |
126 |
127 | - [systemd DBUS API](www.freedesktop.org/wiki/Software/systemd/dbus/)
128 |
129 |
130 | show
23 |
24 | ### Unsorted Lists
25 |
26 | ```
27 | * item one
28 | * item two
29 | * item three
30 |
31 | ```
32 |
33 | ### Numbered Lists
34 |
35 | ```
36 | 1. item one
37 | 1. item two
38 | 1. item three
39 | 1. item four
40 | 5. item five
41 |
42 | ```
43 | ### Code Blocks
44 |
45 | ```
46 |
47 | ```
48 | insert code here
49 | ```
50 |
51 | ```
52 |
53 | ### Headings
54 |
55 | ```
56 |
57 | # H1
58 | ## H2
59 | ### H3
60 |
61 | ```
62 |
63 | ### URL's
64 |
65 | ```
66 |
67 | [Link Name](Link URL)
68 |
69 | ```
70 |
71 | ### Images
72 |
73 | ```
74 |
75 | 
77 | ```
78 |
79 | ### Text Formatting
80 |
81 | ```
82 |
83 | **This is Bold**
84 | *This is italics*
85 | `This is code`
86 |
87 | ```
88 |
89 |
90 | show
97 |
98 |
99 | ```
100 | ***
101 |
102 | ## Title
103 |
104 | show
105 |
106 |
107 | ```
108 | code here
109 |
110 | ```
111 |
112 |
113 |
117 | show
124 |
125 |
126 | ```
127 | ***
128 |
129 | ## Title
130 |
131 | * Add Description here
132 |
133 | show
134 |
135 |
136 | * Add lists, tips, links, etc here
137 |
138 |
139 |
140 |
144 | show
151 |
152 |
153 | Relative links are recommended in your Markdown files when linking to internal content.
154 |
155 | ```markdown
156 | [Link to a header](#awesome-section)
157 | [Link to a file](docs/readme)
158 | ```
159 |
160 | Absolute links have to be updated whenever the URL changes (e.g., repository renamed, username changed, project forked). Using relative links makes your documentation easily stand on its own.
161 |
162 | [*Read more about relative links.*](https://help.github.com/articles/relative-links-in-readmes/)
163 |
164 |
165 | show
173 |
174 |
175 | Rendering PDF
176 |
177 | GitHub supports rendering PDF:
178 |
179 | 
180 |
181 | [*Read more about rendering PDF.*](https://github.com/blog/1974-pdf-viewing)
182 |
183 |
184 | show
191 |
192 |
193 | When creating a repository, GitHub gives you the option of adding in a pre-made license:
194 |
195 | 
196 |
197 | You can also add them to existing repositories by creating a new file through the web interface. When the name `LICENSE` is typed in you will get an option to use a template:
198 |
199 | 
200 |
201 | Also works for `.gitignore`.
202 |
203 | [*Read more about open source licensing.*](https://help.github.com/articles/open-source-licensing/)
204 |
205 |
206 |
207 | show
214 |
215 |
216 | In full Markdown documents **read-only** checklists can now be added using the following syntax:
217 |
218 | ```
219 | - [ ] Mercury
220 | - [x] Venus
221 | - [x] Earth
222 | - [x] Moon
223 | - [x] Mars
224 | - [ ] Deimos
225 | - [ ] Phobos
226 | ```
227 |
228 | - [ ] Mercury
229 | - [x] Venus
230 | - [x] Earth
231 | - [x] Moon
232 | - [x] Mars
233 | - [ ] Deimos
234 | - [ ] Phobos
235 |
236 | [*Read more about task lists in markdown documents.*](https://github.com/blog/1825-task-lists-in-all-markdown-documents)
237 |
238 |
239 | show
246 |
247 |
248 | For example, to syntax highlight Ruby code in your Markdown files write:
249 |
250 | ```ruby
251 | require 'tabbit'
252 | table = Tabbit.new('Name', 'Email')
253 | table.add_row('Tim Green', 'tiimgreen@gmail.com')
254 | puts table.to_s
255 | ```
256 |
257 | This will produce:
258 |
259 | ```ruby
260 | require 'tabbit'
261 | table = Tabbit.new('Name', 'Email')
262 | table.add_row('Tim Green', 'tiimgreen@gmail.com')
263 | puts table.to_s
264 | ```
265 |
266 | GitHub uses [Linguist](https://github.com/github/linguist) to perform language detection and syntax highlighting. You can find out which keywords are valid by perusing the [languages YAML file](https://github.com/github/linguist/blob/master/lib/linguist/languages.yml).
267 |
268 | [*Read more about GitHub Flavored Markdown.*](https://help.github.com/articles/github-flavored-markdown/)
269 |
270 |
271 |
272 | show
6 |
7 |
8 | Changes correspond to branches with the naming schema "gerrit_<change
9 | number>". So you can
10 |
11 | git checkout gerrit_12345
12 |
13 |
14 | show
19 |
20 |
21 | Sometime you want to delete a change to make it invisible for everyone
22 | (for example when you did commit an unencrypted secret...). This is
23 | possible only via the SQL interface which you can enter with
24 |
25 | ssh :29418 gerrit gsql
26 |
27 | and issue a delete with:
28 |
29 | update changes set status='d' where change_id='';
30 |
31 |
32 | show
37 |
38 |
39 |
40 | It is a bit non-obvious to search for text in commit messages. When just
41 | searching "message:" no results are given. This is because "status:"
42 | auto-defaults to a useless values. So you need to specify "status:" with
43 | a useful value:
44 |
45 | status:merged message:critical bugfix
46 | status:open message:Patch
47 |
48 |
49 | show
54 |
55 |
56 |
57 | #### Bad pack header
58 |
59 | This happens from time to time if you do not garbage collect and hit the
60 | open file limit. To solve: trigger a garbage collection
61 |
62 | ssh :29418 gerrit gc
63 |
64 | #### Unpack failed: error Missing unknown xxx
65 |
66 | Solution here is to abandon the problematic changes. This cannot be done
67 | via the GUI and only by admins
68 |
69 | # Find Gerrit id
70 | ssh :29418 gerrit query xxx
71 |
72 | # Abandon the change
73 | ssh :29418 gerrit gsql -c "update changes set open='N',status='A' where change_id=;"
74 |
75 |
76 | show
4 |
5 |
6 |
7 |
8 |
9 |