sjas

This is an approach to generate dynamically a JSON representation of an OID tree (=an(y) SNMP MIB) using mibdump.py of python pysmi.

We will generate a flat list of OID objects (oid_catalog.json) + hierarchical json tree (oid_tree.json) with "."-separated nodes of RFC 1213 MIB.

1. Setup + get MIB(s) as JSON

$ pip install pysmi
# walk into and/or create a new directory you run the following command in
$ mibdump.py --destination-format=json --generate-mib-texts --build-index --mib-stub= RFC1213-MIB

sjas

tl;dr:

• mostly, hosts ignore the mss sent
• most of the interesting behaviour comes from the extremes: mss=1 and mss=1440
• setting mss=(an atypical value, say 1275 or 1411) ought to spot hosts that simply reflect MSS values
• setting mss=1024 apparently will spot a bunch of (Microsoft?) hosts returning MSS=956
• passively, mss=1220, 1360, 1410 may help identify CDN/non-CDN nodes inside yahoo/edgecast, google, facebook respectively

Longer version: captured SYN+ACK+MSS values:

Variation is less than I initially thought; just enough for me to notice

sjas

channel operator quick reference

direct discussion about administrative action away from the main channel and into #reddit-diabetes-ops to minimise disruption. our -ops channel is the place where users should come to ask for our help. examples:

• any sort of operator request or discussion of channel administration in the main channel
• PMs asking why a ban was set
• reports of harassment (unless the user is confiding in you)
• any request for operator action

changing channel access permissions

sjas

class DotGenerator(Visitor):
    def __init__(self):
        super().__init__()
        self.lines = []
        self.next_id = 0

    def make_name(self, node, name=None):
        if name is None:
            name = "n%d" % self.next_id
            self.next_id += 1

sjas

package main

import (
	"net/http"
	"database/sql"
	"fmt"
	"log"
	"os"
)

sjas

Installing Ubuntu 16.04 with btrfs using debootstrap

Partition layout

First, create a GPT partition table.

1. boot partition, label: EFI, flags: boot + ESP; size: 1GB, format to FAT32;
2. root partition (label: root), must same size on all devices!
3. swap partition.

sjas

if _, err := os.Stat("/path/to/whatever"); os.IsNotExist(err) {
	// path/to/whatever does not exist
}

if _, err := os.Stat("/path/to/whatever"); err == nil {
	// path/to/whatever exists
}

sjas

An Ansible summary

Jon Warbrick, July 2014, V3.2 (for Ansible 1.7)

Configuration file

intro_configuration.html

First one found from of

sjas

// Parsing arbitrary JSON using interfaces in Go
// Demonstrates how to parse JSON with abritrary key names
// See https://blog.golang.org/json-and-go for more info on generic JSON parsing

package main

import (
	"encoding/json"
	"fmt"
)

sjas

Introduction

A Go version of The Perl Cookbook

The Perl part is copyrighted by O'Reilly & Associates yet freely available.

This copy is based on http://pleac.sourceforge.net/pleac_perl.data

Strings