Thread Info
  • State Suggested Answer
  • Locked Locked
  • Replies 7 replies
  • Answers 1 answer
  • Subscribers 5 subscribers
  • Views 15889 views
  • Users 0 members are here
Options
Suggested
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

How to ignore my ISPs DHCP MTU of only 576?

jdmoore0883

Hello Sophos Experts!


My issue is as follows... My ISPs DHCP server is setting my external interface's MTU to 576. While an MTU of 1500 should (and does) work, whenever I change the MTU in the WebAdmin UI, it gets reset to 576 by DHCP. Yes, getting the ISP to fix their equipment *IS* the larger, overall solution here, but I cannot rely upon them for such a fix...

How can I alter this behaviour? How can I get my Sophos Gateway to ignore the DHCP packets MTU? How can I permanently, manually override that external interface's MTU?



This thread was automatically locked due to age.
Parents
  • 0

    Search  the forum for mtu 576 and you will find what you are looking for.

  • 0 in reply to darrellr

    You must mean any number of posts and links referring to editing the /var/chroot-dhcpc/etc/defaults.conf file... Right?

    Let me rephrase my original question then....

    Since any CLI edits will void the support, is there any SUPPORTED solution to this issue yet?

  • 0 in reply to jdmoore0883

    Yes, that's the one.  And no, not that I know of.  I would not lose sleep over changing this option and continuing to get support, but that is just my opinion.  The "proper" method, would be to rebuild/restore using 404 and skip 405 for now.  Or, if you have support you are worried about losing, why not use it and ask Sophos support?  Seriously, not trying to be daft, just wondering.

  • 0 in reply to darrellr

    IPersonally, I do not have support, I am just using the Home version.That being said, I also do some consulting work, and one of my customers has Sophos (which is how I got introduced to it in the first place). Due to the (somewhat comical/idiotic) nature of our contract, I cannot contact Sophos on their behalf. So any/all Sophos work involving me with them has to come from me alone. Normally, this isn't an issue as most (99%) issues they raise work out to be PEBKAC-type issues. But every now and again, something like this pops up, and I need to find a "Supported" solution without involving my customer.

Reply
  • 0 in reply to darrellr

    IPersonally, I do not have support, I am just using the Home version.That being said, I also do some consulting work, and one of my customers has Sophos (which is how I got introduced to it in the first place). Due to the (somewhat comical/idiotic) nature of our contract, I cannot contact Sophos on their behalf. So any/all Sophos work involving me with them has to come from me alone. Normally, this isn't an issue as most (99%) issues they raise work out to be PEBKAC-type issues. But every now and again, something like this pops up, and I need to find a "Supported" solution without involving my customer.

Children
No Data
Unfiltered HTML