Home / user-2253

bortzmeyer's questions

Martin Hope
bortzmeyer
Asked: 2013-04-08 05:43:55 +0800 CST
  • 5

When I start Net-SNMP from systemd, there is no error message but the daemon does not run:

% sudo systemctl start snmpd
%

When I start it from the command line, it runs:

% sudo /usr/sbin/snmpd

and answers to SNMP queries.

If I add the debug flags (-LSdd), I see that the daemon launched by systemd is killed immediately after:

Apr  7 15:37:50 localhost snmpd[1298]: NET-SNMP version 5.7.2
Apr  7 15:37:50 localhost snmpd[1298]: Received TERM or STOP signal...  shutting down...

The service file is the default one of the Arch Linux package:

[Unit]
Description=Simple Network Management Protocol (SNMP) Daemon
After=syslog.target network.target

[Service]
Type=forking
ExecStart=/usr/sbin/snmpd 
ExecReload=/bin/kill -HUP $MAINPID

[Install]
WantedBy=multi-user.target

If I add RemainAfterExit=yes in the service file, snmpd works but the machine no longer starts properly (no DHCP client, for instance)

The system is an up-to-date Arch Linux, the version of the package is:

Name           : net-snmp
Version        : 5.7.2-3

There is an old Arch Linux bug report apparently for this very bug: https://bugs.archlinux.org/task/32258?string=snmp&project=1&type%5B0%5D=&sev%5B0%5D=&pri%5B0%5D=&due%5B0%5D=&reported%5B0%5D=&cat%5B0%5D=&status%5B0%5D=open&percent%5B0%5D=&opened=&dev=&closed=&duedatefrom=&duedateto=&changedfrom=&changedto=&openedfrom=&openedto=&closedfrom=&closedto=

arch-linux
Martin Hope
bortzmeyer
Asked: 2012-10-08 05:54:57 +0800 CST
  • 1

I'm trying to filter on some parts of the payload, for an IPv6 packet with extension headers (for instance Destination Options).

ip6tables works fine with conditions like --proto udp or --dport 109, even when the packet has extension headers. Netfilter clearly knows how to jump over Destination Options to find the UDP header.

Now, I would like to use the u32 module to match a byte in the payload (say "I want the third byte of the payload to be 42). If the packet has no extension headers something like --u32 "48&0x0000ff00=0x2800"̀ (48 = 40 bytes for the IPv6 header + 8 for the UDP header) works fine, If the packet has a Destination Options, it no longer matches. I would like to write a rule that will work whether the packet has Destination Options or not.

I do not find a way to tell Netfilter to parse until the UDP header (something that it is able to do, otherwise --dport 109 would not work) then to leave u32 parse the rest.

I'm looking for a simple way, otherwise, as BatchyX mentions, I could write a kernel module doing what I want.

linux
Martin Hope
bortzmeyer
Asked: 2010-08-26 00:47:26 +0800 CST
  • 4

For aesthetic reasons (I prefer when there is a strict one-to-one mapping between URL and pages), I do not like the fact that http://www.example.com/index.html and http://www.example.com/ yield the same content with two different URLs. I would like to have http://www.example.com/ as the canonical one.

The obvious solution:

Redirect permanent /index.html /

is wrong (endless loop).

A better solution? It seems surprisingly difficult.

http apache-2.2 url
Martin Hope
bortzmeyer
Asked: 2009-07-17 00:36:52 +0800 CST
  • 4

I have a Subversion repository where a directory was moved once. I want to send to someone only a part of the repository, which includes this directory.

I believe I have read and understood the manual.

What I tried:

svnadmin dump /home/Subversion-Repository | \
   svndumpfilter include new-name /new-name /foo/bar/old-name > something.svn

svnadmin create /new/repos
# Create directories foo/bar and new-name
svnadmin load /new/repos < something.svn

But it fails:

<<< Started new transaction, based on original revision 5944
svnadmin: File not found: transaction '5944-4l4', path 'new-name/myfile'
     * editing path : new-name/myfile ...

What surprises me is that, in the full dump (without going through svndumpfilter), there is a revision which adds the files at the new place:

Node-path: new-name
Node-kind: dir
Node-action: add
Prop-content-length: 10
Content-length: 10

but svndumpfilter does not keep it. So, the first revision mentioning a file under new-name is 'Node-action: change' and not 'Node-action: add' and it fails. Why?

An Unix shell script to reproduce the problem at will is available.

[I asked the question on the Subversion mailing list but the message was not distributed, probably eaten by an overzealous spam filter.]

UPDATE: I tested Insyte's suggestion. Both svndumpfilter2 and svndumpfilter3 fail. Both do not even check the argument, you can give them a non-existing repository, they would not complain.

With svndumpfilter2, modifying my script to use ${SVNDUMPFILTER2} ${REPOS} other/new-name/bar foo/old-name/bar > ${DUMP}:

<<< Started new transaction, based on original revision 7
svnadmin: File not found: transaction '8-8', path 'other/new-name/bar/myfile'
     * editing path : other/new-name/bar/myfile ...

With svndumpfilter3, modifying my script to use ${SVNDUMPFILTER3} --untangle=${REPOS} other/new-name/bar foo/old-name/bar > ${DUMP}:

<<< Started new transaction, based on original revision 7
svnadmin: File not found: transaction '8-8', path '/other/new-name/bar/myfile'
     * editing path : other/new-name/bar/myfile ...
svn