Re: Timeout settings
Hello, Thank you very much for the answer. That clears it up. I reckon specifying '-K' on dbclient would then do the same as ServerAliveInterval. Cheers, Daniel On Wed, 18 Mar 2020 at 14:58, Matt Johnston wrote: > Hi Daniel, > > -K is equivalent to the OpenSSH ClientAliveInterval. The server will send > traffic to check that the connection is open. > > -I will disconnect if there is no traffic for a certain time interval. It > won't try to send any traffic over the connection, it just passively looks > at what traffic is being sent. > > Note that it seems that currently -K messages will cause the -I idle timer > to reset which isn't right, there's a pull request > https://github.com/mkj/dropbear/pull/90 which I will merge soon. > > Cheers, > Matt > > > > On Wed 18/3/2020, at 7:22 pm, Dániel Fancsali > wrote: > > > > Hello, > > > > First of all, let me just say this: awesome piece of software. Cheers! > > > > I am, however, a bit confused about the idle/keepalive settings. I have > been working with OpenSSH quite a bit, and do understand the concepts > around ServerAlive and ClientAlive as well as the TCPKeepAlive settings. > But I still struggle to wrap my head around -K and -I in dropbear. It's a > tad bit unclear which one maps to which one; or in other words, which one > happends on what layer. > > > > Maybe, my mistake here is trying to understand those in the context of > the OpenSSH settings, but on some level, it's the same protocol. > > > > So, looking at the code, I think this is what happens: > > - Setting -Kx will send an ssh packed every x seconds, and if there's no > answer 3 times in a row, it considers the connection to be dead. So this is > essentially ServerAlive/ClientAlive mechanism. > > - Specifying -Iy would say, if there's no incoming or outgoing data for > y seconds, it considers the connection dead. So this is sort of the others > side of the TCP keepalive coin. > > > > Is my understanding correct? If not, can someone please shed some light > on this for me? > > > > Regards, > > Daniel > >
Re: Timeout settings
Hi Daniel, -K is equivalent to the OpenSSH ClientAliveInterval. The server will send traffic to check that the connection is open. -I will disconnect if there is no traffic for a certain time interval. It won't try to send any traffic over the connection, it just passively looks at what traffic is being sent. Note that it seems that currently -K messages will cause the -I idle timer to reset which isn't right, there's a pull request https://github.com/mkj/dropbear/pull/90 which I will merge soon. Cheers, Matt > On Wed 18/3/2020, at 7:22 pm, Dániel Fancsali wrote: > > Hello, > > First of all, let me just say this: awesome piece of software. Cheers! > > I am, however, a bit confused about the idle/keepalive settings. I have been > working with OpenSSH quite a bit, and do understand the concepts around > ServerAlive and ClientAlive as well as the TCPKeepAlive settings. But I still > struggle to wrap my head around -K and -I in dropbear. It's a tad bit unclear > which one maps to which one; or in other words, which one happends on what > layer. > > Maybe, my mistake here is trying to understand those in the context of the > OpenSSH settings, but on some level, it's the same protocol. > > So, looking at the code, I think this is what happens: > - Setting -Kx will send an ssh packed every x seconds, and if there's no > answer 3 times in a row, it considers the connection to be dead. So this is > essentially ServerAlive/ClientAlive mechanism. > - Specifying -Iy would say, if there's no incoming or outgoing data for y > seconds, it considers the connection dead. So this is sort of the others side > of the TCP keepalive coin. > > Is my understanding correct? If not, can someone please shed some light on > this for me? > > Regards, > Daniel
Timeout settings
Hello, First of all, let me just say this: awesome piece of software. Cheers! I am, however, a bit confused about the idle/keepalive settings. I have been working with OpenSSH quite a bit, and do understand the concepts around ServerAlive and ClientAlive as well as the TCPKeepAlive settings. But I still struggle to wrap my head around -K and -I in dropbear. It's a tad bit unclear which one maps to which one; or in other words, which one happends on what layer. Maybe, my mistake here is trying to understand those in the context of the OpenSSH settings, but on some level, it's the same protocol. So, looking at the code, I think this is what happens: - Setting -Kx will send an ssh packed every x seconds, and if there's no answer 3 times in a row, it considers the connection to be dead. So this is essentially ServerAlive/ClientAlive mechanism. - Specifying -Iy would say, if there's no incoming or outgoing data for y seconds, it considers the connection dead. So this is sort of the others side of the TCP keepalive coin. Is my understanding correct? If not, can someone please shed some light on this for me? Regards, Daniel
