Recommendation: Compact Flash Card

  • Hello all,

    I'd like to ask you for some CF Card recommendations. Since I'm having this troubles of RO/RW problems with current CF Card, I'd like to switch back to 2.0 but I don't have a backup and therefor I want to buy a new CF Card. My current CF has 4GB. Any recommendations?


  • Netgate have posted some experience here:

    Technical note: Netgate recently changed from utilizing SanDisk CF cards to Kingston CF cards, due to a negative interaction between the way in which SanDisk reported space availability on their cards and the actual space available. It caused a soft read error (NID_NOT_FOUND) to occur when reading/writing to the card, which was not really a problem but is annoying to the end user. Transcend cards have the same problem. If you wish to learn more about this problem, start here.

    "start here" is a pfSense forum post at:,41312.msg226353.html#msg226353

    I have recently received some of the Kingston CompactFlash elite pro 133X 4GB cards. I tried writing the 4GB image to them, but they were a little to small (less than decimal 4GB 4,000,000,000 bytes). It is a bit annoying that the makers of these cards are advertising a size and then not even making the card that big in decimal, let alone making it 410241024*1024 bytes. The 2GB image fits on it fine of course ;)

    I notice that the prebuilt Alix systems from Netgate have 4GB cards in them, but with the 2GB image pre-loaded - I guess they have the same problem getting the 4GB image to fit.

    It seems that the pfSense 2.1 FreeBSD 8.3 issue with slow mounting read-only is not specific to any particular CF card brand. So at this point there is no brand recommendation to work around that.

  • Netgate Administrator

    Transcend cards have the same problem.

    Interesting. I am using mostly Transcend 4GB cards (the cheapest type) and have never seen this error.
    I have also used a few Sony cards when they were on speacial offer near me, no problems.

    I always use the 1GB image just because it writes to the card faster. There is no advantage to using the larger image. The larger card has more sectors for ware levelling but it's debatable whether that's any real advantage.

    It's worth noting that there is no point in buying a card with a high transfer rate. These support UDMA modes but pfSense disables it, all cards run at PIO speeds.

    @Szop, I assume you have seen the work around JimP recently added to the 2.1 snapshots for the RO/RW problem?
    Edit: I see you have.  ;)


  • @stephenw10: Damn it! The info about "It's worth noting that there is no point in buying a card with a high transfer rate" came a little bit to late for me :D. Well, it's just ~35€ so everything is fine.

    It's this one:

    I went for the 8GB CF card since I was afraid of the 4g limitations on some CF cards.

    Yes, I tried out the work around of JimP and it worked perfect, but something slowed down the firewall again and I'm kind of tired to remount it every time again. I'll just switch back to 2.0.1 and wait until a stable, hopefully properly working with my CF card, 2.1 version is out :).

    I was always wondering what the difference is between those 1g-4g versions, thanks for clearing this up.

    Thanks for your support and all replys,

Log in to reply