OpenWRT: Allowing PPTP clients to connect

If the worst outcome of trying to upgrade the router firmware is that you might brick it, surely the second worst is when your wife is unable to connect to her VPN when a work emergency demands it. Late on Monday night, Aish sat down to get some work done for a presentation she had the next day … [Read more…]

TP-Link Archer C7: How not to NAT

I have had the TP-Link Archer C7 wireless router for a few months now. Although the hardware in this router is great bang-for-buck, the stock firmware leaves much to be desired. I run a number of servers out of my homelab which requires the router to be configured with port based NAT rules. I found … [Read more…]

Trip to New York

I haven’t been actively involved with campus recruiting since I joined VMWare, mainly because the timing never really worked out. With Aish and me doing long distance till Oct 2013, and then being busy through 2014 with figuring out her job, parents visiting, there was never really a chance to get involved. This year too … [Read more…]

SPF for Email Authentication

Sender Policy Framework (SPF) allows receiving mail servers to authenticate whether the SMTP server originating the email is authorized to send email for the domain. Most email servers will check if the SPF record for a domain exists and if it doesn’t, there are chances that the email can get flagged as spam. Until recently, … [Read more…]

Running a Mail Server

Email (internet messaging) has been around for almost as long as the internet itself. SMTP (Simple Mail Transfer Protocol) allows for designing email systems that are open, non-federated and distributed across the internet. Unfortunately, the architects of this system did not foresee how email spam, trojans, worms and computer viruses would make life miserable for … [Read more…]

Extending an LVM partition on a Ubuntu VM

Logical volumes allow for flexibility of resizing system partitions on the fly without any downtime. This is a pretty nice feature to have in Guest OS since one does not have to worry too much about allocating the right amount of disk upfront. In a previous life, I have spent many a waking hour reinstalling … [Read more…]

Configuring unbound as a local DNS server

Unbound is a validating, recursive, and caching DNS resolver written in C and much more lightweight than its predecessor, BIND. It was developed with a focus on security and an assumption that every host it interacts with could be malicious. BIND, in comparison, has become too bloated, slow and complicated to maintain. I expect to … [Read more…]

Upgrading the home lab to ESXi 6.0

VSphere 6.0 was released last week so I decided to give it a spin in my home lab. It comes loaded with a lot of features that might not be useful in a smaller virtual environment: virtual volumes, long distance vmotion, VSAN 2.0, etc but it does include significant scalability improvements for various subsystems in the vmkernel. … [Read more…]

Backing up VMs on ESXi

After putting together my home server along with its 4 VMs, I wanted to have a way to back them up periodically to a NFS datastore. Given that one of my drives in a ZFS pool failed recently, I realized that not having a backup of the ESXi datastore itself on which the VMDKs were … [Read more…]

Replacing a disk in a zpool

Of late, I have been seeing a number of S.M.A.R.T errors from one of my drives in the zpool. The drives are raw device mapped into the FreeNAS virtual appliance giving them the appearance and functionality of real disks in the virtual appliance. This allows for FreeNAS to be able to collect and display S.M.A.R.T … [Read more…]