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New Member

M train to T train

I have a c1941isr that is subject to bug cscu90521.  It currently has ios 15.4.2.m(4) ios.  The m train md deployment that has the fix is not going to be released until end of march.  But the t train md deployment 15.3.2t2 is currently released and has the fix.  So i'm considering going from m to t train now.  Not sure what the difference between m and t train is and what the concerns would be in a move like this.  The features currently being run on the isr is zbf, site vpn, client ssl vpn and then the standard nat/pat/acl's etc...  Would this be a move that would be recommended or any big deal

Super Bronze

Re: M train to T train


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T is for "Test".  A mainline train, like M, might be more stable.  Bugs can be found in either.

If the current bug, in your M Train, is a show stopper for you, and the only current fix is in a T Train, then you're sort of forced into trying it.

I've used T Train releases, often without any issues, but when I have a choice, I'll run a mainline release.