Johan's questions

Have configured postfix on an EC2 instance. Can send and receive emails locally. Have also configured SES, with verified domain. Outgoing works perfectly well. However, receiving mail to SES returns

<[email protected]>: host inbound-smtp.eu-west-1.amazonaws.com[176.32.109.132]
    said: 550 5.1.1 Requested action not taken: mailbox unavailable (in reply
    to RCPT TO command)

No entry is shown in the postfix log, so I suspect SES is not even trying to talk to my EC2 instance.

dig MX mydomain.com

; <<>> DiG 9.10.3-P4-Ubuntu <<>> MX mydomain.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1395
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;mydomain.com.                        IN      MX

;; ANSWER SECTION:
mydomain.com.         60      IN      MX      10 inbound-smtp.eu-west-1.amazonaws.com.

;; Query time: 77 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Thu Jan 04 13:32:12 UTC 2018
;; MSG SIZE  rcvd: 95

dig mydomain.com

; <<>> DiG 9.10.3-P4-Ubuntu <<>> mydomain.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51289
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;mydomain.com.                        IN      A 

;; ANSWER SECTION:
mydomain.com.         34      IN      A       52.50.184.26

;; Query time: 0 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Thu Jan 04 13:34:10 UTC 2018
;; MSG SIZE  rcvd: 59

I have port 25 open for inbound traffic. I can telnet to it from home. Replace mydomain.com with kummelvagen.se unless you are an evil bot.

What am I missing?

Having a Visual Studio project to deploy to Azure from Jenkins running on GNU/Linux, I'd like to prepare a package with MSBuild in Windows. Something like MSBuild my.csproj /T:Package. This will create a zip file.

Now, how can I deploy this file to an Azure Web App instance over ftp? I was hoping just putting the file in wwwroot would unpack it, but that doesn't seem to be the case.

Any good suggestion is very welcome.

New to Azure, I'm looking for a good way of deploying our apps. The situation is that we build our Java apps inside our network using Jenkins. Each successful build should be automatically published to the production environment on Azure. We cannot have any port opened from our network to Azure other than https. To make it even worse, we need to go through an http/s proxy. Note that we can only deploy compiled war-files. No code is allowed to be published outside our network.

What would be the options in our case?

I'm setting up Jenkins with Pipeline (former Workflow) and trying to configure Multibranch. All documentation I find is about git and svn, but I'm stuck with using Perforce. I have installed all plugins, including p4 (the new Perforce plugin). Setting up a Multibranch job, I'm provided with a dropdown list under Branch Sources called Add source, with only the item called Single repository & branch. If selecting this, here is the description:

Allows a single, fixed branch of some repository to be configured. Not normally used, as it does not allow branches to be detected automatically. Might be used, for example, if you want to build all branches of one repository, and the master branch of a special clone.

For me, automatic detection of branches is essential. What am I missing?

Situation: zfs server over 10GbE p2p at 192.168.201.1 running omnios, debian client at 192.168.201.2. The nfs performs fairly well on big files but horribly slow on small ones. For instance, cp -r /etc /mnt/nfs_mountpoint takes 8 minutes while cp -r /etc /mnt/sshfs_mountpoint to the same machine takes 40 seconds.

I have experimented quite a lot with nfs mount parameters. Currently, the mount looks like this:

zfs:/z2pool/fs on /mnt/shared/fs type nfs (rw,relatime,vers=3,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=192.168.201.1,mountvers=3,mountport=61082,mountproto=udp,local_lock=none,addr=192.168.201.1)

I've been stuck here for weeks now. I won't downvote anything, hence trial n error suggestions are welcome.

Update: I have tried both async and sync with no or little difference.

I want to forward ssh traffic from A port 2222 to B port 22. I do have ipv4 forwarding set to 1 on both interfaces. Still, this does not work. What is wrong?

Machine A: eth0 192.168.0.150 eth1 217.27.166.110

Machine B: eth0 192.168.0.200

iptables -L:

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:http
ACCEPT     icmp --  anywhere             anywhere             icmp echo-request

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     tcp  --  anywhere             192.168.0.200        tcp dpt:ssh state NEW,RELATED,ESTABLISHED

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

iptables -L -t nat:

root@lbpub01:~# iptables -L -tnat
Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination         
DNAT       tcp  --  anywhere             217.27.166.110       tcp dpt:2222 to:192.168.0.200:22

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     tcp  --  217.27.166.110       192.168.0.200        tcp dpt:ssh

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Update

I got help from the nice guys at irc@freenode, so here is my working iptables-save file:

*nat
:PREROUTING ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A PREROUTING -p tcp -m tcp -d 217.27.166.110 --dport 2222 -j DNAT --to-destination 192.168.0.200:22
-A POSTROUTING -o eth+ -j MASQUERADE
COMMIT
*mangle
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
COMMIT
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -i lo -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -p tcp --dport http -j ACCEPT
-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -j DROP
COMMIT

I have a simple rule to point my domain.tld to a local address 192.168.0.205. It takes everything; all subdomains *.domain.tld as well as the main domain itself.

    local-zone: "domain.tld." redirect
    local-data: "domain.tld. IN A 192.168.0.205"

I have my load balancer at 192.168.0.205 so for making requests working internally I need to do this. However, my mail server is located outside this network, so I need to make three exceptions to this; smtp.domain.tld, imap.domain.tld and domain.tld itself. I'd prefer if I just could make those slip through to the ISP's dns, but if that is not possible I can live with having to set their global ip's in my config.

How can I do this? I've tried using transparent instead of redirect but I cannot make it work like I want. I think one of the main problems is to handle the main domain without subdomain prefix.

I have my router connected to the Internet. From the router, I have an ssh tunnel setup like this:

ssh -f tunnelserver.net -L 2000:proxy:8888 -N

This opens the port 2000 on localhost from my router. Now I want this port to be accessible from within my LAN, but it is closed. How can I open it?

I have GatewayPorts yes in /etc/ssh/sshd_config, if that matters.

First, this is strange. I have two laptops running Ubuntu 10.10. On one of them, when connecting my 3G modem, it just works out of the box. For the other one, I need to modprobe option to register it as a GSM modem.

How can I do this at boot?

I want to backup my list of manually selected packages in Ubuntu, without listing packages installed as dependencies. For example,

dpkg --get-selections

returns a complete list of all installed packages, manually selected as well as dependencies. How can I filter dependencies?